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Commentary | 14 November 2017

Leaning in or stepping back? British strategy towards CSDP post-Brexit

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Nick Wright |Teaching Fellow in EU Politics at University College London

Brexit Defence EU Security United Kingdom European Defence

The UK Government’s September 2017 ‘Future Partnership’ paper on foreign and defence policy made clear it sought a post-Brexit relationship with the EU27 ‘unprecedented in its breadth, taking in cooperation on foreign policy, defence and security’. Although lacking specifics, when taken with Theresa May’s Florence Speech it signals a welcome change in tone from the start of the year when she implied that ongoing British defence and security co-operation would be contingent on progress in other areas of negotiation. Instead, this is an unambiguous British commitment to the long-term security of its European allies, reflecting not only their long-standing ties, but also the reality that both sides face the same range of security threats, and need each other’s support to address them. The challenge, though, remains how.

One potential means of facilitating future cooperation is through the CSDP, a component of EU-level co-operation the UK played a significant role in developing. In the 15+ months since the referendum there has been renewed interest among the EU27 in ‘re-booting’ it. Several ambitious new initiatives have been launched including: a new Military Planning and Conduct Capability (MPCC) within the EEAS; a European Defence Fund to promote defence research and inter-operability; a Coordinated Annual Review on Defence (CARD) to ‘enhance strategic convergence’ between member states; and serious efforts to finally launch Permanent Structured Co-operation (PESCO) in defence.

For many years, the UK has urged EU partners to get their collective act together to build serious military capabilities. These developments suggest this may finally be happening, particularly given Paris and Berlin’s support for these efforts. However, given CSDP’s chequered progress since its launch in 1999, the question is whether the UK could use it as a means of future engagement in security and defence co-operation with the EU. The contention here is that it both could and should.


Could the UK participate in the CSDP in future?

Brexit will end British obligations that include permanent involvement in the institutional structures and decision-making processes of the CFSP and CSDP. However, this does not automatically preclude any future involvement in defence and security co-operation. There is a clear political desire on both sides to maintain the closest possible ties. For example, the UK has expressed a willingness to pay into the European Defence Fund. For their part the EU27 wish to encourage co-operation, particularly given the UK’s importance as one of Europe’s two ‘big’ military powers.

As the examples of Norway and Serbia demonstrate, moreover, non-membership is no hurdle to co-operation. Norway frequently coordinates with the EU on a range of foreign policy questions and has formal agreements for participation in CSDP missions and cooperation with the European Defence Agency. In Serbia’s case, despite its unfinished accession process, it has nonetheless participated in several CSDP missions including EUNAVFOR Atalanta and EUTM Somalia.

Such states have very little influence over CSDP decision-making processes, however, and it is difficult to imagine the UK accepting such a situation. Obviously it will seek to influence partners – most notably France and Germany – through its extensive bilateral diplomatic network and, where appropriate, in other multilateral settings such as the UN, NATO and OSCE. However, these cannot match the EU in terms of the level and intensity of interactions that take place, and the problem for the UK is clear: it will no longer be in the room when decisions are taken.

This is not insurmountable, though. The UK could seek continued participation in the Political and Security Committee and/or key CSDP working groups, for example. While it could not expect a vote (or veto), observer status and/or speaking rights might be feasible. For their part, the EU27 have a pragmatic interest in maintaining British involvement given its extensive expertise and resources, and the credibility it adds to EU foreign and security policy. Both sides would therefore benefit from finessing the UK’s ongoing institutional involvement.


Should the UK participate in the CSDP in future?

A key issue for the UK is whether Brexit will negatively affect its security and defence interests in Europe. While NATO and the transatlantic alliance remain the foundations of its defence strategy, neither are as certain as they once were. The Trump Administration’s ambivalent attitude to NATO has left many European states questioning the reliability of the US security guarantee in the longer term. The UK’s traditional response to potential American disengagement has been to push European allies to make stronger commitments to burden-sharing and London previously considered CSDP a means of achieving this. The UK should therefore welcome the latest drive for improved EU military capacities as many of these would in theory also be available to NATO.

At the same time, some EU members, particularly the Baltic States, are concerned that the proposed development of CSDP might actually weaken the transatlantic alliance. A strong argument can therefore be made that continued British involvement in CSDP in whatever form is in its strategic interest, particularly if it helps it promote complementarity rather than competition with NATO. In doing so, the UK will also provide reassurance to east European states with which it has close defence ties and which have traditionally looked to it for leadership. Finally, it signals to Washington that the UK remains an active and relevant security partner in Europe, whilst underscoring the value of European efforts at enhanced defence collaboration.



The UK’s strategic interest in maintaining a secure and stable Europe remains unchanged since Brexit, as do the range of threats and challenges facing it and its EU partners. Consequently, London should actively support renewed efforts to develop and enhance CSDP, maintain the closest practical co-operation, including exploring the opportunities afforded by PESCO, and where possible seek some form of continued participation in existing policy and decision-making structures. Although the UK has stepped back from CSDP in recent years, it may find post-Brexit that it becomes crucial to sustaining a British commitment to European defence and security.


The opinions articulated above represent the views of the author(s), and do not necessarily reflect the position of the European Leadership Network or any of its members. The ELN’s aim is to encourage debates that will help develop Europe’s capacity to address the pressing foreign, defence, and security challenges of our time.