UK-French Defense and Security Cooperation Post-Brexit

France and the United Kingdom play a very special role in the defence and security of Europe. These two countries are the main military powers of the European continent: together they account for just under half of the European defence budget and capabilities, they are the only nuclear powers, and have demonstrated the will and ability to undertake expeditionary military operations. They are also the only ones with close ties with Africa and the Middle East because of their colonial past and, finally, the only ones aiming to lead on the global stage, in accordance with their seats as permanent members of the United Nations Security Council.

The military alliance between these two countries is long-standing: it dates back to the Entente Cordiale of 1904 and to the two World Wars during which they fought side by side for the freedom of the European continent. A new impetus was given to this deep defence and security relationship with the Lancaster House Treaties, signed in 2010 as a follow-up to the 1998 St-Malo Declaration. At this occasion, they reaffirmed their interdependence to the point that they do not see ‘a situation in which the vital interests of one of the parties could be threatened without those of the other’. France and the UK have also committed themselves to an ambitious programme of operational, industrial and nuclear cooperation aimed, in a context of budgetary austerity, at drawing all the synergies from this strategic convergence recertified by France’s return to the integrated NATO command structure. This partnership, which complements UK- France defence in multilateral structures, such as, but not limited to, NATO and the European Union, is crucial for both countries.

The UK and France collaborate on defence and security in a variety of ways. In the operational field, the two countries have created a non-permanent Combined Joint Expeditionary Force (CJEF), which has been successfully tested in multiple training exercises and continues to be refined. Officer exchanges and joint training have reached an unprecedented level. In industrial matters, numerous projects have been initiated, notably in the field of missiles, a sector now fully integrated around the MBDA group. In the nuclear field, our two countries have set up decisive joint simulation and research infrastructures to maintain, at a lower cost, the viability of our nuclear deterrence. The success of this cooperation, in an area as sensitive and as much linked to national sovereignty, shows the closeness and depth of the UK-France partnership.

The defence cooperation formalised by the Lancaster House agreements is supplemented by high-level security cooperation, whether it operates informally on a bilateral basis or through dedicated European instruments, such as the Passenger Name Record (PNR), the Schengen Information System, the Europol Agency or the European arrest warrant.

This partnership is all the more central for the security of the European continent as the threats we face have never been greater: Islamist-inspired extremism; Russian pressure on Europe’s eastern border and its destabilising actions striking at the heart of our democracies; the emergence of new powers threatening the current international order; the weakening of North African and Middle Eastern states and increased migration flows within the region and to Europe, which is bolstering nationalist parties; the emergence of new threats in cyberspace; and the rise of populism. These all threaten the democratic freedoms and multilateralism to which the UK and France are committed.

It is in this context too that developments in American foreign policy, namely a strategic shift towards the Pacific, reinforced by President Trump’s unilateral and isolationist policy, are shaping a world in which Europe will have to defend itself, and pay the price for its security and freedom.

UK-France cooperation has therefore never been so valuable, yet it also has never been so fragile. Even before Brexit, some aspects of this partnership were unsatisfactory. This is particularly true in the industrial field, where several structuring projects, notably aimed at promoting the interoperability of our aircraft carriers, developing the next generation of nuclear submarines and producing a medium- and long-endurance surveillance drones, have failed. The Future Combat Air System (FCAS) project also seems compromised.

With regard to military operations, the model for joint operations envisioned by the Lancaster House Treaties has not been repeated since the military intervention in Libya, largely because of different political priorities (France alone assumed most of the burden of its interventions in Mali and Central African Republic).

This remains the case today, even though the UK and France have since cooperated in the Levant, targeting both ISIS and the chemical weapons capabilities of the Syrian regime.

These limitations are in part due to budgetary restrictions and differences in the approach of both countries’ defence industries, but also to the divergent views held by France and the UK on the respective roles of the European Union and NATO in defence and security, and diverging national political priorities in this regard. Brexit aggravates these difficulties. While it does not call into question the framework for bilateral UK-France cooperation, it does affect multilateral cooperation, which is particularly central in security matters, and could also complicate industrial cooperation.

Beyond its practical consequences, Brexit amplifies tensions inherent in the UK-France relationship. It will now be more difficult for France to reconcile its ambitions for European defence (recently reinforced by the establishment of EU initiatives such as permanent structured cooperation [PESCO] and the European Defence Fund) with its alliance with the UK, especially as France remains keen to involve the UK in this European architecture (which was a strategic objective as much as a pragmatic one). On the other hand, the two pillars of the UK’s foreign policy – the transatlantic relationship and its European anchorage – are being questioned, leaving the country without a clearly defined and designed foreign policy: the ‘Global Britain’ doctrine designed to fill this gap still lacks substance.

Despite these headwinds, it is crucial to give new impetus to the UK-France relationship, in order to ensure the security of the European continent. To do this, we make three core recommendations.

First, everything must be done to ensure that Brexit does not jeopardise European security. Security issues must be separated and protected from the rest of the Brexit negotiations.

A privileged partnership must be established to maintain police and judicial cooperation and exchanges of data, which are crucial in the fight against terrorism and organised crime. To this end, it seems possible to revise the status of third countries. It will also be necessary, especially for the UK, to find compromises on the most difficult issues, such as the jurisdiction of the ECJ and the degree of involvement in decision-making processes. The cross-border cooperation between France and the UK that was established by the Touquet and Sangatte agreements must also be preserved.

It is then necessary to fully implement the Lancaster House Treaties. In this respect, the full operationalisation of the Joint Expeditionary Force, which could usefully be articulated with the new European Intervention Initiative (EII), is of particular importance. As political impetus has always played a major role in the success of UK-France cooperation – but also in its failures – it seems desirable to strengthen strategic dialogue by creating an annual UK-France Defence and Security Council, supplemented by a more regular ‘2+2’ dialogue comprised of foreign and defence ministers, and a ‘Quint’ dialogue between the heads of the main intelligence services.

Finally, we must adapt our partnership to prepare ourselves, together, for the uncertainties the future will bring. Collaboration between our intelligence services would benefit from being more formally structured, in particular to make progress in the field of cybersecurity, which must become a new pillar of our partnership. A common doctrine, joint development of key technologies in data encryption, the detection and identification of cyber attacks, and cooperation on artificial intelligence are needed. This new pillar should contain confidentiality and exclusivity clauses making it possible to overcome the difficulties posed by the Five Eyes alliance, in which the UK, but not France, participates.

A common strategic vision must be developed in R&D, identifying key technologies and opportunities for collaboration and leading to joint capacity development. In this respect, the continuation of the FCAS project, for which our two countries have unique competencies and common operational requirements, appears particularly decisive for the strategic autonomy of the European continent, even if this project will undoubtedly have to be brought closer, in the long term, to the Franco-German combat aircraft project.

The UK-France defence and security relationship is strong.

That does not make it immune to internal and external forces which can erode ties between the two countries. There is no more pressing moment in time to reinvigorate and revitalise the relationship, to the benefit of the UK, France, and Europe as a whole.