Leggi in ItalianoOn 19 May 2025, in London, the European Union and the United Kingdom agreed on a Security and Defence Partnership. The document addresses a tension that has been apparent since Brexit: the United Kingdom has left the European Union, yet it remains one of the key actors in the security of the continent. Institutional separation has changed neither geography nor strategic interests, nor has it made common threats disappear.
Adopted at the first EU–UK summit since Brexit, the partnership establishes a fairly broad framework for cooperation. It covers support for Ukraine, sanctions coordination, maritime security, cybersecurity, the protection of critical infrastructure, space security and responses to hybrid threats. It also provides for cooperation on foreign information manipulation and interference (FIMI), as well as exchanges on emerging technologies, including the use of artificial intelligence in security and defence.
At the institutional level, the document provides for six-monthly consultations on foreign and security policy, an annual dialogue specifically devoted to security and defence, and the possibility of involving the United Kingdom in certain EU initiatives. London may be invited to participate in missions and operations under the Common Security and Defence Policy (CSDP). Cooperation with the European Defence Agency and in the framework of Permanent Structured Cooperation (PESCO) projects is also envisaged, particularly in relation to military mobility.
One legal point deserves emphasis: the partnership is a politically, rather than legally, binding instrument. It does not amend the EU Treaties, give the United Kingdom a role in EU decision-making or grant automatic access to EU defence instruments. Any specific form of participation will have to be agreed in accordance with the applicable rules and procedures. The document also reaffirms NATO’s central role in the collective defence of its allies.
What I find particularly interesting is the political significance of this choice. For several years after Brexit, the debate focused mainly on the economic and institutional consequences of the United Kingdom’s withdrawal. Russia’s war against Ukraine has made it even clearer that European security does not stop at the borders of the European Union. The United Kingdom possesses military, technological and intelligence capabilities that are difficult to disregard when discussing the defence of the continent.
The May 2025 partnership acknowledges this reality. Of course, it remains to be seen how much of this political dialogue will translate into operational cooperation, joint programmes and capabilities that can actually be deployed. That is where its practical value will be tested.