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The Future of EU-UK Cooperation on Security and Defence

The UK’s withdrawal from the European Union will bring about profound changes for both the UK and the European Union in the areas of security and defence. Moving forward, the two blocs must agree on new arrangements that will enable them to foster cooperation. It is in the EU’s interest to prevent a rupture of its close ties with the UK, while at the same time it must safeguard its interests. Following the Political Declaration on the future EU-UK relationship the EU and the UK need to establish a ‘broad, comprehensive and balanced security partnership’ based on geographic proximity and shared threats. As such, both parties can continue close cooperation on common security and defence challenges, with regard to the autonomy of the EU and UK’s sovereignty.

The European Union is committed to fostering its future relations with the UK. The UK will become a third country to the EU. A partnership in the fields of security and defence must be mutually beneficial for both EU and UK citizens. Brexit bears many risks for the UK in political, strategic, and economic terms. Not maintaining existing defence and security arrangements with the European Union would significantly weaken the UK’s position on the global stage. For instance, the UK will no longer hold a seat on the European Council or the Foreign Affairs Council (FAC) and will be unable to directly influence the EU’s decisions in the areas of security and defence. Furthermore, as a future non-Schengen third country, the UK will not have access to the Schengen Information System (SIS), the largest and most widely used information sharing system for security and border management in Europe. Therefore, the UK must avoid isolation after the end of the transition period, which would make London seek for closer collaboration with its traditional partners, such as the United States and Canada within the framework of the North Atlantic Treaty Organization (NATO). As the future of the UK-US relations is still unclear, the UK does not have the interest in breaking the existing EU cooperation on security and defence.

Moreover, the remaining 27 member states will aim to strengthen the EU’s security and defence capabilities, while respecting their respective defence traditions, to overcome the progressive withdrawal of the US as the main ally of the Union and to counter the ambitions of the other geopolitical competitors, such as Russia and China.

Fostering cooperation

Both the EU and UK have strong interests in remaining partners in the areas of security and defence after Brexit. The security partnership embedded in the Political Declaration should include issues like security and defence, foreign policy, cooperation in areas of mutual interest, law enforcement and judicial cooperation in criminal matters. The EU and UK must continue to pursue many shared interests, such as the common objectives of the Common Security and Defence Policy (CSDP). The UK should be invited to participate in CSDP missions, while the rules of the future EU-UK cooperation need to be shaped by a clear foreign policy approach.

As CSDP includes humanitarian and rescue missions, conflict prevention and peacekeeping, disarmament operations, and post-conflict stabilisation, European foreign and security policy should continue to be characterised by multilateralism, negotiated solutions and the application of international law. The UK should not have decisional powers but should keep access to programmes and funds in the areas of defence, for example the European Defence Industrial Development Programme (EDIDP).

An agreement on the rights and obligations of the UK in defence initiatives such as the European Defence Agency (EDA), the Permanent Structured Cooperation (PESCO) and Galileo is of crucial importance. Access to these programmes should be allowed but limited in order to preserve the strategic autonomy of the EU. It is therefore imperative that during the transition period, member states of the European Union and the UK assist each other when needed, and that the former stands firm and united. Furthermore, the continuation of joint education and training, the strengthening of cooperation in cyber-security, industry and research, hybrid warfare, the fight against international terrorism, capability development, and protection of privacy is essential to effectively address Europe-wide challenges.

Furthering European military integration

The coronavirus outbreak must not jeopardise the crucial improvements in EU’s defence and security cooperation that have occurred over the past years. The withdrawal of the United Kingdom from the EU can prove to be a new momentum to further deepen European military integration. It can be an opportunity for the 27 member states to cooperate more in these domains. Existing initiatives, such as PESCO and the European Defence Fund (EDF), need to be strengthened in order for the EU to grow its influence in the global arena. PESCO can facilitate the development of member states’ defence capabilities through an increasing involvement in joint procurement projects, joint education and training and joint capacity building, while the EDF can accelerate research and innovation in the areas of security and defence and promote the integration of defence policies of member states. This budget must be made available for a real European agenda.

The role of the UK within other institutions 

By leaving the EU, the UK will lose access to multiple pacts and agreements in the areas of security and defence. Nevertheless, the UK remains a strong military power sharing the European Union’s core values of peace, democracy, protection of human rights. It must uphold its commitment to closely cooperating with the EU on common challenges such as terrorism, cybersecurity issues like cyberwarfare, and crises in Europe’s neighbourhood. With this regard, as written in the EU-UK Political Declaration, the UK must lay the foundation for renewed cooperation on external action to safeguard citizens and strengthen security, including through the other main international organisations and military alliances, i.e.  the United Nations (UN), particularly the Security Council, and NATO, respectively. Furthermore, the UK has signed and will maintain multiple bilateral agreements with several member states.

Potential impact of Brexit on EU’s security and defence arrangements

Due to the coronavirus pandemic, it has been estimated that the European Union’s defence budgets may lose dozens of billion euros in 2020 and 2021. The UK is one of Europe’s biggest military powers. The EU will therefore lose a strong military partner, that previously held the largest military budget in the EU, owning about 20% of the EU’s military capabilities. For this reason, the EU should coordinate and further deepen investments in defence research and development (R&D), while strengthening its existing programmes and initiatives. In this respect, the size of the EDF should be such as to effectively contribute to Europe’s strategic autonomy, while the Neighbourhood, Development and International Cooperation Instrument (NDICI) should embody the main tool to effectively administer the financing of the European Union’s external action to pursue the objectives and principles of its external action.

Towards enhanced cooperation

Brexit will undoubtedly have a negative impact on the UK’s and the EU’s defence and security capabilities. Nevertheless, crucial factors such as geographic proximity, and the sharing of values and principles of peace, freedom and mutual assistance must play a pivotal role in shaping the future EU-UK cooperation in security and defence. New dialogues on foreign policy are expected to take place and become the norm to foster a special third-party cooperation, aiming to keep the UK closely involved in this field. It is in both the EU’s and the UK’s interest to set up a system of mutual coordination and consultation to share information and support this foreign policy relationship.

Published in January 2021

The Future of EU-UK Cooperation on Security and Defence

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