General Principles in EU External Relations Law and the EU as a Global Actor: An Introduction

Table of Contents: 1. Introduction – 2. General principles in EU external relations law: constructing a constitutional space for the EU’s external action. – 3. Overview of the contributions

Abstract: This Introduction to the Special Section examines the role of general principles of law (GPs) in EU external relations and their significance in shaping the European Union’s normative identity as a global actor. Although GPs occupy a central place in the EU legal order, their function, scope, and systematic deployment in the external domain remain insufficiently theorised. Recent case law of the Court of Justice demonstrates that GPs increasingly mediate tensions between autonomy and effectiveness, between political discretion and legal accountability, and between the Union’s internal constitutional values and their external projection. This Introduction also highlights that the contributions in this Special Section explore these developments along three themes: the EU as a value-driven global actor; the EU as a coherent and consistent actor; and the EU as an effective actor responding to contemporary international challenges. Together, they show how GPs fulfil both structural and systemic functions in delineating the constitutional framework for the Union’s external action, and how they contribute to understanding the EU’s value-oriented external approach.

Keywords: general principles of EU law – EU external relations – normative identity of the EU – constitutionalisation of EU external action – autonomy – Court of Justice of the European Union.

1.   Introduction

General principles (GPs) play a crucial role in the EU legal order. They provide justifications for the application of concrete rules, they can be used as aids to interpretation and they also act as standards for judicial review. They have been important tools in constructing and articulating the EU’s distinct constitutional identity and furthering the integration project, thus expressing its core values.[1] While the CJEU has had frequent recourse thereto, many questions still persist regarding their very definition, function, scope as well as methods for identification. As Advocate General (AG) Mazák has eloquently put it: ‘[I]t lies in the nature of general principles of law, which are to be sought in the Platonic heaven of law than in the law books, that both their existence and their substantive content are marked by uncertainty’.[2] The EU has developed its own constitutional principles such as direct effect, supremacy and autonomy; there are also GPs common to all the Member States such as the rule of law and equality. 

GPs are of cardinal importance in EU external relations law. In this context, they shape the legal framework for the EU’s interactions with the wider world. Despite their importance, the role of GPs in EU external relations law remains under-explored and under-theorised.[3] In the literature, various attempts have been made to classify them.[4] In the specific field of EU external relations law, Marise Cremona has identified a set of principles that are structural – ‘in the sense of defining and being inherent to the deep structure of the EU’.[5] Structural principles can be further classed into relational and systemic principles.[6] As Cremona explains, relational principles, such as the principle of conferral of powers, the principle of solidarity and the rule of law, structure the relationship between actors or legal subjects.[7] On the other hand, systemic principles, such as coherence, effectiveness and autonomy, are concerned with the operation of the system as a whole and with building the EU’s identity as a global actor.[8]

Furthermore, despite their centrality in EU law and in EU external relations law more specifically, the influence of general principles on the EU’s actorness is largely absent in the burgeoning debate on the normative identity of the EU as a global actor.[9]What do general principles, as these are developed and employed in the area of EU external relations law, say about the Union as an international legal actor? More importantly perhaps, as principles embody the values of a given legal order,[10] and contribute to forming its ‘philosophical, political and legal substratum’,[11] fundamental questions arise pertaining to the relationship between principles and the values enshrined in Articles 3(5) and 21 TEU.[12]

Internally, the relationship between values and general principles has come under closer judicial scrutiny due to the EU’s rule of law crisis. More particularly, over time, it seems that structural principles, such as the rule of law, are becoming more clearly grounded in respect for common values.[13] In the Budget Conditionality cases the CJEU made it clear that ‘Article 2 TEU is not merely a statement of policy guidelines or intentions, but contains values which are an integral part of the very identity of the European Union as a common legal order, values which are given concrete expression in principles containing legally binding obligations for the Member States’.[14] More recently, in a remarkable defence of the direct justiciability of Article 2 TEU as a standalone provision, AG Ćapeta took note of the process of constitutionalisation at the level of EU primary law stressing the key role of Article 2 TEU in fleshing out in legal terms ‘[t]he vision of what a good society is in the EU constitution’ and painting ‘a picture of a constitutional democracy that respects human rights’.[15] The AG explained that many of the values of Article 2 TEU have been given more concrete expression in (constitutional) principles and that ‘basic constitutional principles are often, at the same time, political and legal’.[16]

While the relationship between GPs and the distinct constitutional space that the Union occupies has always been part and parcel of EU constitutional law discourse,[17] the legal contours of the external aspects of the Union’s constitution remain largely under-developed in the literature.[18] In light of the recent judicial developments pertaining to the EU’s ‘constitutional framework’[19] and of the links between (general) principles and values, questions arise as to the external dimension of that framework. What role do GPs play in the constitutional blueprint for the EU’s external action? How do these principles articulate in legal terms the values that are supposed to govern the EU’s interaction with the outside world and how do the inherent tensions between these values translate at the level of GPs? Reflecting on the function of GPs in EU external relations law allows us to ask important questions about the nature and identity of the EU both as a constitutional polity and an international legal actor. As Nic Shuibhne has aptly remarked: ‘Structural principles […] give us critical new tools to hold a deeper conversation about the constitutional evolution of the Union across different parts of the EU’s legal order, both discretely and more universally’.[20]

Against this backdrop, the special issue, which stems from a joint T.M.C. Asser Institute – Centre for the Law of EU External Relations (CLEER) conference on the same topic that took place in December 2024, contributes to a more refined conceptual and doctrinal understanding of the role of general principles in EU external relations law. It does so by focusing on the overarching question of ‘how do GPs shape the EU’s normative identity as a global legal actor?’ The special issue is comprised of an introduction and nine substantive contributions. All contributions elucidate different aspects of the overarching question. Three broad themes emerge: i) general principles and the EU as a value-driven global actor; ii) general principles and the EU as a consistent and coherent global actor; iii) general principles and the EU as an efficient global actor tackling modern challenges.

In the rest of this introduction, we will provide some general remarks pertaining to recent developments in relation to the operationalisation of general principles by the CJEU in the field of EU external relations (Section 2), as well as a summary of the contributions contained in this special issue (Section 3). 

2.   General principles in EU external relations law: constructing a constitutional space for the EU’s external action

An important starting point in the discussion of the (evolving) role of GPs in EU external relations law is that they function differently in the external dimension.[21] Internally, they have been utilised by the Court in order to facilitate the process of integration, as the EU’s raison d’etre.[22] By way of contrast, the absence of an end-goal in EU external relations entails that their role in that context is much more process-oriented than substantive. The primary role of GPs here is to establish and preserve a framework within which the EU’s political institutions interact with each other, the MS as well as the wider world and formulate the EU’s foreign policy on the basis of broadly-defined objectives.[23] As Azoulai observes: ‘The concern herein is constructing the EU itself as a credible and effective actor than constructing any substantive order’.[24] This function corresponds to the need to leave the institutions’ ample room for manoeuvre in shaping foreign policy. The CJEU has been reluctant to interfere with this room for manoeuvre and it has repeatedly stressed that in the conduct of external relations, EU institutions enjoy a broad discretion in policy decisions, which necessarily implies policy choices.[25]

Another point that deserves attention here pertains to the operation of the principle of autonomy. The principle of autonomy has played a major role in constructing the legal space of the EU’s external action and mediating the EU’s relations with the outside world.[26] The Court has repeatedly emphasised its understanding of the EU as a legal order that is autonomous both vis-à-vis the MS and international law.[27] Exploring the role that GPs play externally inevitably involves exploring the role that international law plays in delimiting EU external action and thus, examining the relationship between the principle of autonomy and the Union’s brief to contribute to ‘the strict observance and the development of international law’ under Article 3(5) TEU.[28] AG Spuznar has pointed to the difficult co-existence of the two main narratives in EU external relations law when, in his Opinion in the Rina case, he argued that: ‘The co-existence of two obligations, namely that of contributing to the observance of international law and that of ensuring respect for the autonomy of the European legal order, can create tensions which the Union must resolve’.[29]

How do more recent jurisprudential developments relating to GPs fit in this picture? First, these developments bring into sharp focus existing tensions between autonomy and effectiveness – two key aspects of the EU’s identity as a global actor. This tension is most acute in the Court’s line of case-law concerning the EU’s participation in forms of judicial dispute settlement outside the context of the Treaties. In the past, this tension was resolved by the CJEU decidedly in favour of autonomy. There is a long line of case-law, including most prominently Opinion 2/13[30] and, more recently, Achmea,[31] where autonomy was couched in abstract and uncompromising terms – thereby establishing a very high threshold for the EU to participate in international dispute settlement.[32]

However, more recently, in Opinion 1/17 (CETA), both the AG and (implicitly) the Court, seem to have relied on Article 3(5) TEU in order to put more weight on the EU’s commitment to international law – thereby highlighting how the principle can be used in order to construe autonomy more narrowly and thus, to allow the EU to participate effectively in the international scene. AG Bot used Article 3(5) TEU in order to bolster his argumentation that the mechanism for settlement of investor-State disputes under the Comprehensive Economic Agreement between Canada and the EU (CETA) is compatible with the principle of autonomy of EU law. According to the AG:

[T]he Court should interpret the principle of autonomy of EU law not only in such a way as to maintain the specific characteristics of EU law but also to ensure the European Union’s involvement in the development of international law and of a rules-based international legal order … Under Article 3(5) TEU, ‘in its relations with the wider world, the Union shall … contribute to … the strict observance and the development of international law …’ That last objective logically means that the European Union should favour initiatives and control mechanisms which enhance the effectiveness of the international treaties to which it is a party.[33]

While not expressly relying on Article 3(5) TEU, the Court espoused this approach in the judgment:

It is […] precisely because of the reciprocal nature of international agreements and the need to maintain the powers of the Union in international relations that it is open to the Union […] to enter into an agreement that confers on an international court or tribunal the jurisdiction to interpret that agreement without that court or tribunal being subject to the interpretations of that agreement given by the courts or tribunal of the Parties.[34]

Thus, the CETA Opinion attests to the potential of utilising the provision in order to limit the far-reaching effects of past broad constructions of the concept of autonomy and thus, to create a more harmonious relationship between EU and international law

It bears noting here that recent case-law highlights how, in the external context, effectiveness is to be understood more broadly as effectiveness of the EU’s external action rather than effectiveness of EU law. In Spain v Commission (Kosovo),[35] the Court was faced with the question of Kosovo’s participation in an EU agency. According to Spain, such participation was precluded on the grounds that the EU has not recognized Kosovo as an independent State and thus, Kosovo could not be considered a ‘third country’ within the meaning of the relevant EU regulation. The Court found, inter alia, that the principle of effectiveness entails that an entity not recognized as a sovereign State should be treated as a ‘third country’ within the meaning of that provision ‘while not infringing international law’.[36] The Court relied on the purpose of ‘ensuring the effectiveness’ of Article 35 (2) of the BEREC Regulation in order to argue that Kosovo should be considered as falling within the scope of the concept of a ‘third country’ within the meaning of the provision. 

What the Court seems to be suggesting here is that such a broad interpretation is needed in order to ensure that the EU functions as an effective actor on the global stage – which is no longer dominated by States alone. This echoes a point made earlier by the General Court to the effect that not accepting the possibility of the Union concluding agreements with territorial entities other than States ‘would be to create a legal vacuum in the European Union’s external relations’.[37] This arguably entails broadening the scope of the principle of effectiveness. In the context of interpretation of EU law, the principle of effectiveness dictates that where a provision of EU law is open to different interpretations, preference must be given to the one which ensures that the provision retains its effectiveness.[38] Considerations of effectiveness of the type asserted here would entail protecting the effectiveness of the EU external action – as opposed to the full effect of EU law.[39] This inserts in the interpretative process the need to take into account (foreign) policy considerations, namely, how to ensure the functionality of the Union as an international actor.

Another major development relates to the crucial role that GPs have played in fleshing out the external dimension of the Union’s constitutional blueprint as a Union of values both internally and externally.[40] The Court does not seem to be agnostic towards substantive core values even in the field of external action and questions of accountability of the Union towards those affected by its external action are increasingly coming to the foreground. More particularly, the limited jurisdiction of the CJEU – and hence, the limited legal accountability – in CFSP matters is in tension with the identity of the EU as a union based on the rule of law and raises questions about the scope of judicial review in that field.[41] Thus, it is not surprising that in a number of recent cases, the Court has started exploring the exact contours of its jurisdictional ‘carve-out’. In this line of case-law, GPs have been an important tool in the Court’s incrementally extensive interpretation of its jurisdiction. More particularly, GPs have been instrumental in curbing CFSP exceptionalism and ensuring the area’s embeddedness within the broader EU (constitutional) law framework. As the Court stressed in KS and KD:

[T]he inclusion of the EU constitutional framework means that the basic principles of the EU legal order also apply in the context of that policy. These include, in particular, respect for the rule of law and fundamental rights, values expressed in Article 2 TEU and given concrete expression to in Article 19 TEU, which require that both EU and Member State authorities be subject to judicial review.[42]

At the same time problems persist. In KS and KD, the Court ruled that it has authority over CFSP acts or omissions that are not directly related to ‘political or strategic choices’ made in the context of the CFSP[43] without however articulating clear criteria for distinguishing between legal questions amenable to review on the one hand and purely political or strategic choices on the other. The Court’s lack of reasoning in KS and KD has attracted criticism in the literature.[44]

By way of contrast, AG Ćapeta’s Opinion in the case highlights the potential for utilising GPs as a methodological tool for defining the boundaries of the EU Courts’ jurisdiction in the CFSP.[45] It is worth briefly summarizing the AG’s arguments here. The AG read the case-law on the progressively narrower construction of the Court’s jurisdictional limitation in the field of the CFSP through the lens of GPs. The AG stressed that post-Lisbon the CFSP is part of the EU constitutional regime, and showed how GPs underpin that line of case-law and are thus, applicable in any case requiring the interpretation of the Court’s jurisdiction in the CFSP.[46] The AG understood the jurisdictional ‘carve-out’ as being necessary to ensure that EU courts do not ‘replace policy choices made by competent political institution’.[47] The AG added however a very important ‘fundamental rights’ safeguard in the task of determining which choices should be left exclusively to the political process. According to the AG:

[I]n constitutional democracies, policy choices are not unlimited. In a Union based on the rule of law it could not have been the intention of the authors of the Treaties to allow for breaches of fundamental rights in the CFSP. As the breach of a fundamental right cannot be a policy choice, the EU courts must be able to control whether that limit was crossed.[48]

The Court, however, did not take up the proposal to automatically extend judicial review to CFSP acts or omissions involving fundamental rights violations. This seems like a missed opportunity. The AG’s Opinion shows how GPs can be used as a methodological tool for delimiting policy choices in the (constitutional) law of foreign relations and thus, for providing much-needed clarity and legal certainty.[49]

More broadly, recent case-law attests to the crucial role that GPs can play as tools for mediating the space between judicial deference to political choices in complex foreign policy issues and the need to comply with the Union’s values both internally and externally. A case is point is the Venezuela v Council judgment[50] where the Court ruled that third States can be regarded as a ‘legal person’ within the meaning of Article 263(4) TFEU for the purpose of bringing an action for annulment to challenge restrictive measures provided that the rest of the conditions of Article 263(4) TFEU are fulfilled. GPs played a prominent role in the Court’s line of reasoning. On the basis of a contextual and teleological interpretation of Article 263(4) TFEU, the Court the provision should be interpreted in the light of the EU’s values and principles governing its external action. It found that the principle of effective judicial protection is an integral part of the rule of law. In turn, the rule of law constitutes one of the founding values of the Union as well as a guiding principle of its external action (Article 21 TEU) including the CFSP (Article 23 TEU)[51]. On this basis, the Court concluded that interpreting Article 263(4) TFEU ‘in the light of the principles of effective judicial review and the rule of law militates in favour of finding that a third State should have standing to bring proceedings, as a legal person’ – provided that the rest of the conditions set out therein are fulfilled.[52]

Interestingly, the Council here put forward an argument on the basis of (lack of) reciprocity. According to the Council allowing third States standing to challenge restrictive measures before EU courts could unduly restrict the EU in the conduct of its international relations - as there is no guarantee that the EU would be able to challenge similar national measures adopted by those States. [53] The Court swiftly dismissed the argument and stressed that the obligation of the Union to ensure the rule of law cannot in any way be made subject to conditions of reciprocity.[54] The Court here essentially argued that the possible political disadvantages of recognising a third State as a legal person for the purposes of an action for annulment bear no relevance to the legal question of whether a third State is entitled to have access to EU courts. In deciding the latter question, GPs that reflect the values of the Union, including the rule of law and effective judicial protection, are of cardinal importance. 

Overall, it seems that the Court’s case-law attests to the ‘normalization’ trend that foreign relations law is undergoing, namely the idea that there is an expansion of the judicial reach over foreign relations matters.[55] In this respect, it has been noted in the literature that ‘for the last decades domestic judicial practice has been heading – slowly, contradictorily, but constantly – towards the expansion of the courts’ competence to adjudicate [foreign relations] issues, both in common law and in civil law jurisdictions’.[56]

The above analysis underscores the value of GPs as a means for operationalising the Union’s values also in the realm of external affairs and as a tool for consolidating the image of the EU as a confident global actor with a distinct commitment to upholding its foundational values in shaping its relations with the outside world. 

3.   Overview of the contributions

The contributions to the Special section all address a specific dimension of the role of GPs in the EU’s external relations. The overall message flowing from the collective set of contributions is threefold. First of all, the contributions highlight a persistent gap between the EU’s formal commitment to foundational principles (such a democracy, human rights, proportionality) and their practical application in external relations. This reveals a systemic challenge: balancing legal accountability with the EU’s need for operational autonomy in a complex geopolitical landscape. Secondly, several authors argue that general principles rarely function as self-standing legal norms but instead shape the interpretation of other rules. This results in the idea that principles act as flexible frameworks, enabling the EU to navigate tensions between legal rigidity and contextual adaptability. Thirdly, the contributions collectively reveal how fragmentation – between EU institutions, legal orders, and global actors – complicates the application of principles. This fragmentation risks undermining the EU’s constitutional resilience.

Thomas Verellen’s paper, ‘Democracy at the Borders: Analysing the Role of Democratic Principles in EU External Relations Law’, first of all, argues that while democracy is enshrined as a fundamental value in the EU Treaties (Article 2 TEU), its constitutional significance remains limited compared to other principles like conferral, institutional balance, or proportionality. The paper demonstrates that democracy functions primarily as a weak background principle in EU law, informing judicial interpretation but rarely serving as a direct yardstick for reviewing secondary EU law. The analysis highlights that the CJEU has not recognised democracy as a self-standing general principle of EU law. Instead, democracy influences the interpretation of other principles – especially institutional balance – without operating as an independent ground for annulment. The paper underscores the historical reluctance to democratise the EU’s institutional framework and the comparatively limited powers of the European Parliament as the EU’s main democratic body. Verellen concludes that meaningful democratisation of EU external relations requires strategic litigation based on specific Treaty provisions and, ultimately, substantive Treaty reform to strengthen democracy’s constitutional standing. General principles of EU law, such as institutional balance, often take precedence over democracy in judicial reasoning.

This is followed by Samantha Besson’s paper, ‘Equity as a General Principle in EU External Relations Law’, which explores the evolving but under-theorised role of equity in international and EU law, particularly in the context of EU external relations. Equity, understood as a principle that both ‘adjusts justice’ and ‘differentiates equality’ in context, has gained prominence in contemporary international and EU law, yet its theoretical treatment remains fragmented and often conflated with equality or solidarity. Besson argues that equity is at a crossroads: while it is experiencing a renaissance in practice, its potential is hampered by a sterile opposition between legality and equity, and by the tendency to over-legalise or de-legalise equity, risking its ‘decadence’. She proposes that equity should be understood as a bridge between law and justice, enabling the alignment of legal norms with moral considerations. In international and EU law, equity’s role is even more critical due to the unique challenges of these legal orders – such as the absence of a centralised global legislature, the diversity of subjects, and the need for distributive and corrective justice in transnational contexts. The paper emphasises that equity should act as a greater counterweight to the rule of law in international and EU law than it does domestically. This is because the rule of law in these contexts faces significant challenges, including power disparities, the conflation of subjects and officials, and the lack of separation of powers. Equity can help address these issues by ensuring that legal norms are applied in a way that accounts for material inequalities and specific circumstances, thereby preventing the rule of law from becoming a mere ‘rule of rules’. Besson concludes by advocating for the institutionalisation and organisation of equity reasoning in international and EU law. This involves ensuring that equity is not reduced to a technical or economic standard, but rather is integrated into legal reasoning as a principled and constrained form of moral judgment. By doing so, equity can enhance the legitimacy and effectiveness of international and EU law in addressing complex issues of justice.

Jarne de Geyter then follows with a paper on ‘Respect for Human Rights as a General Principle of EU External Relations Law: Between de jure Obligations and de facto Standards’. He examines the tension between the EU’s legal obligations to uphold human rights in its external actions and the practical application of these obligations by the CJEU. While the EU Treaties and the Charter of Fundamental Rights explicitly bind the EU to respect human rights in all its actions – including external relations – the Court often adopts a deferential approach, granting EU institutions significant discretion in balancing human rights with political, economic, and strategic interests. This contribution highlights that this deferential scrutiny risks creating a gap between the EU’s de jure human rights obligations and the de facto standards applied in practice. Although the EU remains legally bound by human rights, the CJEU’s leniency – especially in areas like international agreements and the CFSP – allows for greater flexibility, potentially at the expense of effective human rights protection. De Geyter argues that while the EU’s broad discretion is justified by the complexities of external relations, it must still operate within the outer boundaries of fundamental rights, such as the essence of rights and absolute prohibitions (e.g., torture, slavery). Ultimately, the paper questions whether the CJEU’s approach ensures meaningful judicial protection for individuals, given the high thresholds for challenging EU acts and the strict standing requirements. It underscores the need to reconcile the EU’s political leeway with its foundational commitment to human rights and rule of law principles.

The question of the role of the CJEU returns in Katja Ziegler’s contribution, which critically examines the CJEU’s Grand Chamber judgment in KS and KD (2024) on the scope of judicial review in the EU’s Common Foreign and Security Policy (CFSP). While the CJEU affirmed its jurisdiction in principle, it did so through a narrow, text-bound interpretation of Articles 24(1) TEU and 275 TFEU, introducing a controversial ‘political questions’ doctrine to exclude review where acts are ‘directly related to political or strategic choices’. Ziegler’s main point is that the Court missed a crucial opportunity to articulate a principled constitutional approach grounded in EU general principles – such as the rule of law, fundamental rights, and effective judicial protection. Concretely, she highlights three key missed opportunities: 1) using general principles to inform a coherent, hierarchy-sensitive interpretation of Treaty provisions; 2) addressing structural gaps in judicial protection, particularly in light of the CFSP’s evolving operational scope; and 3) reinforcing the EU’s constitutional resilience by clarifying the primacy of core values (Article 2 TEU) over procedural exclusions. Ziegler critiques the Court’s reliance on a political questions doctrine as potentially undermining the rule of law and complicating future ECHR accession.

Andrea Ott’s contribution, entitled ‘The Unity in EU International and External Representation: A Principle, an Objective or Nothing at All?’, examines whether unity in international/external representation functions as a general principle or merely an objective in EU external relations law. The paper argues that unity is neither a self-standing principle nor a clearly defined Treaty objective, but rather an explanatory concept that supports the application of other general principles, such as sincere cooperation (Article 4(3) TEU) and consistency (Articles 13(1) and 21 TEU). Ott traces the evolution of unity in international representation, highlighting its origins in the Ruling 1/78 and its later connection to the duty of cooperation and the principle of consistency. While the Court of Justice of the EU (CJEU) has occasionally referred to unity as a ‘principle’, it primarily serves to clarify the conditions and objectives of sincere cooperation, particularly in the context of mixed agreements and the EU’s coherent global presence. The paper furthermore explores whether unity could be transposed to the horizontal level (between EU institutions) to address the fragmentation of EU external representation, which is characterised by the involvement of multiple actors (e.g., Commission, Council, High Representative) and a variety of instruments (e.g., international agreements, non-binding arrangements). Ott concludes that unity in international/external representation is not a self-standing principle but operates as an underlying aim that guides the interpretation and application of sincere cooperation and consistency. Its role is limited by the precise attribution of powers to specific actors and the detailed procedural rules governing external representation, leaving little room for general principles to fill gaps or provide broad guidance.

Another perhaps emerging principle is that of equivalence. In her contribution ‘Equivalence as an Emerging General Principle of EU External Relations Law’, Monica Spatti explores the role of the principle of equivalence in EU external relations. This principle allows the EU to recognise that a third country’s regulatory standards are comparable to its own, facilitating market access and cooperation while safeguarding EU policies and values. The contribution argues that equivalence, though not explicitly mentioned in the Treaties or formally recognised by the CJEU, is increasingly functioning as an emerging general principle of EU external relations law. Spatti analyses the application of equivalence across several sectors, including financial services, data protection, food safety, and environmental protection. In financial services, equivalence decisions enable third-country service providers to operate in the EU market if their home country’s regulations are deemed equivalent to EU standards. Similarly, in data protection, the EU assesses the adequacy of third countries’ data protection laws, allowing data transfers only if the third country ensures a level of protection ‘essentially equivalent’ to that of the EU. The principle also appears in regulations governing food safety, environmental standards, and fisheries, where equivalence ensures that imported goods or services meet EU requirements. The paper highlights that equivalence serves multiple functions: it protects EU policies and values, promotes international cooperation, and prevents conflicts between legal systems. While some critics view equivalence as a form of unilateralism or protectionism, Spatti argues that it fosters dialogue and shared solutions with third countries, aligning with the EU’s broader objectives of multilateralism and global governance (Article 21(2)(h) TEU). The principle’s flexibility and focus on outcomes rather than uniform rules make it a practical tool for addressing global challenges. Spatti concludes that equivalence, though not yet formally recognised as a general principle, exhibits characteristics of both relational and systemic principles in EU external relations. It governs relationships between the EU and third countries, establishes prerogatives, and helps define the EU’s identity as an international actor. By balancing the protection of EU interests with the promotion of global cooperation, equivalence represents a new form of multilateralism in an interconnected world.

Similar questions return in Francesca Finelli’s contribution entitled ‘Proportionate Sanctions? Balancing Effectiveness and Fundamental Rights before the CJEU’. Finelli examines the role of the principle of proportionality in the judicial review of EU sanctions by the Court of CJEU. The contribution highlights that while sanctions are a key tool of EU foreign policy, their effectiveness must be balanced with respect for fundamental rights, as required by the principle of proportionality (Articles 5(4) TEU and 52(1) of the Charter). Finelli argues that the Court’s review of sanctions varies depending on the type of challenge: when assessing policy measures (e.g., designation criteria), the Court applies a deferential ‘manifestly inappropriate’ test, granting the Council broad discretion. However, when reviewing individual measures (e.g., designations) for alleged fundamental rights violations, the Court conducts a more rigorous, multi-step proportionality test, as seen in the landmark RT France case. This case introduced a four-step approach, emphasising the need to respect the essence of fundamental rights and ensuring that sanctions are temporary and reversible.

Finally, a relatively new general principle seems to have emerged, but is it a principle? Narine Ghazaryan’s contribution, ‘Sustainable Development: A Principle of EU External Relations Law?’, examines whether sustainable development (SD) can be considered a general principle of EU external relations law. While SD is prominently featured in EU treaties (e.g., Articles 3(5) and 21 TEU) and policy documents, its legal status remains ambiguous. The paper argues that SD is not a standalone principle but is closely linked to other foundational principles, such as coherence and environmental integration (Articles 9 and 11 TFEU). Ghazaryan analyses the manifestations of SD in key areas of EU external action – trade policy, development cooperation, and environmental policy – and finds that SD is treated as an overarching objective rather than a binding legal norm. For example, in trade agreements, SD is referenced as a goal but lacks enforceable obligations, while in development cooperation, it is framed broadly to include issues like human rights and security, often prioritising economic growth. The contribution concludes that SD functions as a policy guideline rather than a legal principle, with its implementation dependent on the application of other principles like coherence and integration. Thus, SD remains an aspirational objective rather than a concrete, enforceable principle in EU external relations law. Ghazaryan concludes that while the Court generally defers to the Council’s political discretion, the RT Franceruling offers a structured framework for balancing effectiveness and fundamental rights, potentially setting a precedent for future sanctions litigation.

Finally, given the focus of this Special Section on the EU as a global actor, the question not only is to what extent EU general principles play a role in the Union’s actions at the international level, but also to what extent general principles of international law are taken into account. The paper by Eva Kassoti and Ramses A. Wessel explores the central yet underexplored role of General Principles of International Law (GPIL) in the EU’s legal order, focusing on their interaction with the CJEU. It argues that while GPIL are recognised as a source of international law, their definition, origin, and function remain contested, and their integration into EU law is complex and selective. The authors highlight the Courts’s ambiguous terminology and selective reliance on GPIL, often favouring equivalent EU legal principles to safeguard the autonomy of EU law. They also examine instances where the CJEU resists applying GPIL, particularly when they conflict with the uniformity or effectiveness of EU law. The paper demonstrates that GPIL serve multiple functions in the EU legal order: as a source of EU law, a tool for interpreting and reviewing EU acts, and a bridge between EU and international law. Ultimately, the analysis underscores the nuanced and multifaceted engagement of the EU with GPIL, contributing to both the coherence of the EU legal order and the broader international legal system. The study calls for greater attention to the role of GPIL in EU external relations, emphasising their potential to foster systemic coherence and mutual influence between legal orders.