EU Permanent Structured Cooperation (PESCO): a future role for UK defence?

In an effort to strengthen European defence cooperation and capabilities development, in 2017 EU Ministers agreed to establish Permanent Structured Cooperation (PESCO). Part of a wider package of interlocking defence measures, the mechanism allows willing EU member states to cooperate on specific defence capability projects.

25 EU Member States participate in PESCO, which currently has 60 projects underway.

Third party participation

In November 2020, the EU agreed the rules governing the participation of third states in individual PESCO projects. Under those rules, third countries can exceptionally be invited to participate in a specific PESCO project, provided they can add value and if they meet several political and legal considerations, including support for the EU’s Common Security and Defence Policy.

Involvement of the UK

As an EU member state the UK stayed outside the remit of PESCO after it was first established. Following Brexit, the UK expressed concerns over participation but remained open to cooperation on a case-by-case basis. 

In July 2022 the UK applied to join PESCO’s Military Mobility project. That application was approved by the participating EU states in early October and formal approval was subsequently given at a meeting of EU Defence Ministers on 15 November.

While welcomed by many observers, the UK’s decision to participate in PESCO has revived the debate about UK-EU defence cooperation in the longer term.