In this article I enquire into the sources of legitimacy of the European Union's (EU) Common Foreign and Security Policy. I suggest that as the EU has moved beyond intergovernmentalism in this policy field, it cannot derive its legitimacy solely from the national systems of the member states. It must establish an additional channel of legitimacy, which is derived directly from the EU. Challenging the conventional position on the legitimacy of global governance institutions, I further suggest that EU institutions can only make a reasonable claim to prevail over the member states in this policy field if they contribute to enhance the normative status of the foreign policy. That the co-operative endeavour is mutually beneficial is not a sufficient basis for the legitimacy of EU foreign policy. Drawing on a deliberative perspective, I suggest that we may expect to find two mutually reinforcing sources of legitimacy at the EU level. However, these would mainly contribute to enhance the external legitimacy of the CFPS. Paradoxically, they may at the same time constrain the internal legitimacy of the EU's foreign policy.
This is an Accepted Manuscript of an article published by Taylor & Francis, available online: http://www.tandfonline.com/.