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UK–EU Defence Cooperation and PESCO’s Military Mobility Project

Nervousness around the UK joining PESCO’s military mobility is misplaced. Joining the grouping makes sense from an operational perspective and it aligns with the UK’s envisaged post-Brexit mode of engagement with the EU.

Keeping things moving: the UK joining PESCO's military mobility project will help to ensure the smooth movement of UK troops and kit across Europe. Image: Allied Joint Force Command Naples

In early November, the EU’s High Representative Josep Borrell announced that the bloc had accepted the UK’s request to join the EU’s Permanent Structured Cooperation (PESCO) military mobility project. Among PESCO’s 60 collaborative projects, military mobility has the most countries involved, including 24 EU member states and three non-members, namely the US, Canada and Norway. The Dutch-led initiative aims at simplifying and standardising cross-border military transport logistics by enabling the unhindered movement of military personnel and assets within the borders of the EU, be it via rail, road, air or sea. Specifically, the PESCO project functions as a political platform which keeps member states aware of the work that needs to be done to achieve these objectives.

The issue of UK participation in PESCO initiatives has been sensitive since the country officially left the EU, with some Brexiteers fearing that accepting the conditions for third country involvement in PESCO would fail to deliver on the promise of Brexit and that the UK would be permanently tied to EU defence structures and principles, over which it would have no formal influence. Following a similar line of thinking, some commentators have recently gone so far as to suggest that the UK’s participation in the military mobility project is part of a slippery slope towards joining an EU army. Besides overlooking the pragmatic reasons behind the UK’s decision to join a European military mobility project at a time of war on the European continent and the transatlantic nature of this particular project, these claims fundamentally fail to grasp how PESCO is situated within the European defence architecture and its separation from EU supranational institutions.

Demystifying Cooperation Under the PESCO Framework

The UK joining PESCO’s military mobility project represents the first post-Brexit formal engagement between the UK and the EU's Common Security and Defence Policy (CSDP). While this is undoubtedly a good sign for UK–EU rapprochement, it is still a long way from a return to institutionalised cooperation between the two parties.

In November 2017, 23 EU member states submitted a Joint Notification to the EU Council of Ministers setting out their intention to utilise the PESCO mechanism to further the Union’s CSDP agenda. Situated under the EU’s CSDP umbrella, PESCO is an intergovernmental, voluntary mechanism under which member states agree to make mutual commitments to increase defence spending and improve their military capabilities through various projects. The UK did not sign the Joint Notification and therefore remained outside of PESCO, with no decision-making rights over its governance and projects and no veto over its future strategic direction. Although now a third country outside of the EU, the UK can still participate in specific PESCO projects on a case-by-case basis.

There is high pragmatic value in the UK wanting to improve the speed at which its troops and kit can be deployed across Europe, and attempts to deduce an underlying, long-term political agenda are misplaced

Under the German Council presidency in early 2021, conclusions were reached that regulate the conditions under which third states can exceptionally participate in individual PESCO projects. Third party involvement with PESCO starts with a formal request initiated by the third country applicant. The request should be submitted to the coordinator(s) of the PESCO project in question – that is, to the member state(s), not to an EU institution – and it needs to contain detailed information on the reasons for participating in the project and the scope and form of the proposed participation. Finally, the request must evidence the fulfilment of a set of political, substantive and legal conditions. Namely, the third country applicant should share EU values and principles, as well as the overall objectives of the Union’s Common Foreign and Security Policy; it should provide substantial added value to the PESCO project in question; and it should sign a Security of Information Agreement with the EU and an Administrative Arrangement with the European Defence Agency. The third country's application is then assessed by the project’s participating members, who will decide on whether to accept the third party’s request. Once the participating members have unanimously approved it, they will inform the High Representative and the European Council of their decision. Only following the Council's green light can an invitation to join the project be made to the third state. If the invitation is accepted, an Administrative Arrangement is negotiated outlining contributions and modes of engagement.

There is no ‘one size fits all’ Administrative Arrangement for third countries, and each one is negotiated separately and on an ad hoc basis. Negotiating this agreement might potentially be an area of friction, as it represents the first attempt at putting down in black and white a form of UK–EU post-Brexit engagement. Specifically, the agreement will stipulate rights and responsibilities for the UK as well as introducing a review mechanism to periodically assess whether the UK is meeting those obligations. It is important to demystify it, however. Signing an Administrative Arrangement with the EU is not a political step towards strengthening relationships with the bloc. It should be understood as a licence to unlock ad hoc, project-based cooperation that is intended to fully respect the signatory’s national sovereignty.

The UK’s Rationale for Joining Military Mobility

The UK’s plans to join PESCO’s military mobility are strictly related to the war in Ukraine and motivated by the need to send military kit to Ukraine faster and more easily, as well as equipment and troops to other vulnerable countries in Europe. As explained by the defence minister of the Netherlands, the country lead, ‘Military mobility is perhaps not a very sexy issue but it’s very important. While there is a war, you must know the procedures to get the things you need and the people you need from one place to another’. Thus, there is high pragmatic value in the UK wanting to improve the speed at which its troops and kit can be deployed across Europe, and attempts to deduce an underlying, long-term political agenda are misplaced.

Being able to smoothly move one’s troops across Europe at a time when war has returned to European soil contributes to credible deterrence and reinforces the European pillar of NATO

Besides pragmatic value, the UK participating in a PESCO project would be a move perfectly aligned with the UK government’s envisaged mode of post-Brexit cooperation with the bloc. The UK government has consistently favoured a flexible, ad hoc approach to future defence cooperation with the EU and, most importantly, it has supported EU defence initiatives where they complement NATO activities. PESCO’s military mobility project ticks these boxes. Improving military mobility in Europe has long been one of the flagship areas for EU–NATO cooperation. Indeed, it represents one of those spaces in which the EU and NATO complement each other. Namely, while NATO is able to plan and calculate the military’s needs for transport across Europe, the EU has the legal and regulatory weight to streamline processes as well as available funds and programmes on cross-border mobility. PESCO’s military mobility project epitomises a case where EU action supports NATO efforts and, as such, London’s decision to join is perfectly aligned with UK government policy.

Implications for Anglo-European Defence Cooperation

Just as in every complicated relationship, when it comes to UK–EU engagement, there can be a tendency to overinterpret every gesture. The UK seeking to cooperate with European countries under the PESCO framework could potentially lead to further rapprochement with the EU and closer liaison with its CSDP structures, but it does not have to. For now, all that matters is that it is a sensible move which makes sense from the UK’s perspective. Being able to smoothly move one’s troops across Europe at a time when war has returned to European soil contributes to credible deterrence and reinforces the European pillar of NATO. Perhaps more importantly, the military mobility project does not entail research and development activities, as opposed to most PESCO projects. This therefore avoids a key issue the UK government has been consistently concerned about, namely restrictions over intellectual property rights in EU-led collaborative defence projects.

As such, the UK joining PESCO’s military mobility should not be interpreted as betraying the spirit of Brexit. This sort of cooperation is precisely the type of arrangement envisaged under Brexit: the UK liaising with European states where it is mutually advantageous to do so, and on issues critical to European security – to which the UK has been consistently and exceptionally committed.

The views expressed in this Commentary are the author’s, and do not represent those of RUSI or any other institution.

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