The Duty of Sincere Cooperation and Its Implications for Autonomous Member State Action in the Field of External Relations

  • Peter Van ElsuwegeEmail author


This contribution clarifies the procedural and substantive implications of the duty of sincere co-operation in order to identify the room of manoeuvre for individual Member States at the international stage. Based upon an analysis of the relevant case law of the European Court of Justice, it is argued that the implications of the loyalty principle essentially depend upon the particular context of the EU’s international involvement and, more specifically, upon the implications of a Member State’s intervention for the unity of the EU’s representation and the uniform application of EU law. Whereas this approach is instrumental to achieve the objectives of the EU’s external action as expressed in Article 21 TEU, it may nevertheless have certain paradoxical consequences from the perspective of the Member States.


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Faculty of LawUniversity of GhentGhentBelgium

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