EU Declarations of Competence to Multilateral Agreements: A Useful Reference Base?’

The participation of the European Union alongside its Member States in multilateral agreements can create situations of uncertainty for third parties. In order to deal with this uncertainty, the EU makes a declaration stating the extent to which the international agreement is governed by EU competence. However, these declarations of competence create uncertainty as regards their legal effects and effectiveness. This article aims to examine these issues by analyzing these declarations from a practical perspective.

The first section conceptualizes the declarations, first by establishing their basic features, second, indentifying their legal effects, and third, by identifying a list of problems attached to these instruments. The second section focuses on both the internal and the external practice regarding the declarations of competence. This section highlights how the increasing tendency of the European Court of Justice (ECJ) to rely on the declaration of competence is not mirrored in the external sphere.

In fact, no declaration of competence has ever been invoked by a third party or used by an international court to apportion the responsibilities between the EU and its Member States. The third section assesses the overall effectiveness of the declarations balanced with the problems that they entail.

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