Sticking Together or Drifting Apart: The Future of Franco-British Defense Cooperation

Under heavy gray skies and unsettled seas off the coast of Scotland, French and British naval commanders stand side by side on the bridge of the French amphibious assault and helicopter carrier Tonnerre, observing their land, naval, and air assets operate seamlessly together. It is October 2019, and the event is Exercise Griffin Strike, a bilateral amphibious exercise designed to validate the full operational capability of the maritime component of the Anglo-French Combined Joint Expeditionary Force (CJEF). When the CJEF becomes fully operational by the end of 2020, French and British forces will be able to deploy, at short notice, an “early entry” joint expeditionary force with command options in all three domains. Building on NATO standards and procedures, and regularly assessed through large-scale exercises, the CJEF has increased the ability of both armies to swiftly intervene as a standalone force where and when necessary.

The CJEF is the result of the 2010 Lancaster House treaties, which codified the commitment of the French and British governments to strengthen their bilateral strategic, military, and industrial cooperation. Yet as the 10th anniversary of the treaties approaches in November, the future of Franco-British military and strategic cooperation is uncertain. The United Kingdom’s departure from the European Union earlier this year, coupled with contentious negotiations over the future EU-UK relationship, has created a trust deficit that has put on hold any plans for revitalizing the UK-France bilateral defense partnership.

Yet setting the politics aside, it is clear that a constructive relationship between the United Kingdom and France remains in the national interest of both countries. Moreover, it is the best hope of generating a meaningful European security and defense capability capable of operating effectively both alongside and independent of the United States.

Strategic Convergence with Caveats

The United Kingdom and France are European powers of similar geopolitical standing. Both are nuclear powers; are permanent members of the UN Security Council; and have large, competitive national defense industries. Their defense budgets and number of active duty personnel are relatively equal in size. Taken together, the two countries’ defense budgets account for almost half of all defense spending in Europe. In contrast to many other European countries, public and parliamentary support for the armed forces and defense spending is strong.

Even more importantly, both countries possess a strong strategic culture as well as global interests and responsibilities that drive them to deploy forces overseas in support of their national interests and in defense of international rules and norms. While France may find common cause with Germany on some foreign policy issues—such as the need to take a balanced approach toward Russia—it is in the United Kingdom that it finds a partner of equal political and military standing both politically willing and militarily capable of projecting force abroad. Shared interests include fighting Islamic extremism at home, managing instability in the Middle East, and protecting their commercial activities in the Indo-Pacific.

Admittedly, strategic divergences exist. Within Europe, the United Kingdom prioritizes the threat from Russia to the east, whereas France is more focused on the transnational threats emanating from the south. There are, however, signs that this is changing with the increase of UK forces in the Sahel (within the UN training mission and in support of French-led operation Barkhane) and France’s contributions to NATO’s Enhanced Forward Presence in Lithuania and Estonia (under German and UK command, respectively) as well as Paris’ recognition of Russian malign activity in Africa.

Another significant stumbling block could be their potential divergent approach toward European defense in a post-Brexit context. The United Kingdom is doubling down on its bilateral security relationship with the United States, as well as within NATO, while President Macron advocates for a more sovereign Europe in defense. Yet so long as France continues to exhibit the pragmatic streak that led it to return to NATO’s integrated command structure (in turn enabling the Lancaster treaties) and the United Kingdom demonstrates a desire to keep one foot firmly planted in Europe, these differences can still be overcome and need not be impediments to Franco-British defense cooperation.

Tangible Achievements

Building on these military and strategic similarities and recognizing the limits imposed by growing budget austerity, the United Kingdom and France decided to increase their defense cooperation through the Lancaster House treaties signed in London on November 2, 2010. In the Treaty for Defense and Security Co-operation, Paris and London committed to develop cooperative equipment programs, foster the interoperability of their armed forces, and ultimately deploy together in joint operations, including the “most demanding” ones. These ambitious commitments were fleshed out by concrete initiatives laid out in a joint declaration, including the aforementioned CJEF and the “One Complex Weapon” project. More technical but no less important, the nuclear cooperation treaty foresaw the development of joint simulation facilities intended to guarantee the safety and reliability of nuclear warheads while maintaining secrecy about each country’s nuclear program. To steer this renewed cooperation, the Lancaster House treaties provided for strong governance though an annual summit at the level of the French president and the British prime minister, prepared by a “Senior Level Group” chaired by each countries’ national security advisers.

In the years following adoption of the treaties, tangible progress was made in many areas. Only a few months after their signing, the determination of both countries to enhance their operational cooperation was tested in Libya, where Paris and London were at the forefront, along with the United States, of the international coalition to protect civilians from Gaddafi’s regime. Following this “trial by fire,” France and the United Kingdom increased their operational cooperation in the Levant in the fight against the Islamic State; in the Sahel, where the United Kingdom is providing logistical support to Barkhane (notably through CH-47 Chinook helicopters); in the Baltic States, as part of the Enhanced Forward Presence deployed in Estonia; and even in the Indo-Pacific, where cooperation between the two navies is close.  In the field of capability development, one of the most promising achievements of Franco-British cooperation is the integration of their industrial missile sector through the “One MBDA” strategy. The Future Anti-Surface Guided Weapon (Anti-Navire Léger in French, Sea Venom in English), which is on the verge of completion, constitutes the first concrete example of technological “mutual dependence.” The next flagship program of this cooperation is the Future Cruise/Anti-Ship Weapon, which aims to provide land-strike and anti-ship capabilities to both armies by 2030. Significant progress has also been made in the “Teutates” nuclear program, which includes two joint radiographic-hydrodynamic facilities in France and the United Kingdom. Full operating capacity is expected by late 2022. Beyond these two facilities, which will enable significant economies of scale (around 450 million euros for France), both countries maintain a close dialogue on nuclear issues through the “Joint Nuclear Commission,” created in the early 1990s and which helped produced an in-depth mutual understanding and convergence of each country’s policies and doctrines.

Prospects for Future Cooperation

Considering the likelihood of a difficult security and budgetary environment in the coming decade, the rationale for closer Franco-British defense cooperation grows greater. U.S. expectations that Europe improve its security and defense capabilities and take on more responsibility in its own neighborhood will persist regardless of the outcome of the November election, as the United States faces its own budgetary pressures and is increasingly occupied with the Indo-Pacific. Likewise, though France and the United Kingdom have both committed to maintaining defense spending at or close to 2 percent in the near term, declining GDP due to Covid-19 (and, in the United Kingdom, the economic effects of Brexit) will create downward pressure on budget toplines. There is also growing uncertainty about the future direction of UK security and defense priorities as it has undertaken an Integrated Review whose finalization is in disarray due to the pandemic. In that context, bilateral cooperation is one way to help offset eventual reductions.

Unfortunately, it is not realistic to expect significant progress in Franco-British defense cooperation in the coming months despite the upcoming 10th anniversary of the Lancaster House treaties. Disagreement over a future EU-UK trade relationship makes it difficult for the two entities to commit to a closer security and defense relationship. Many economic and security issues are intertwined, and a UK trade policy that is less oriented toward Europe may diverge with it on certain security issues (e.g., China policy). Likewise, the EU position that all aspects of the future relationship should be dealt with collectively and comprehensively (rather than in a “pick-and-choose” approach) limits the ability of individual members states to strike deals with the United Kingdom in discreet areas such as security and defense, however pragmatic.

Yet once the Brexit process is behind them, France and the United Kingdom should turn the page and jointly consider further strengthening their bilateral defense cooperation, prioritizing progress in four areas:

  • Preserve space for shared capability development. Franco-British industrial cooperation is in danger now more than ever, as recently illustrated by the near collapse of the Future Combat Air System (FCAS) program. Closing the door to such cooperation would be a serious miscalculation, given the weight of the defense budget of both countries, which represent 40 percent of defense expenditure in Europe and more than 80 percent of R&D spending. Divergent capability choices would also significantly weaken their interoperability in the future, as has already been the case regarding their aircraft carriers. Despite—or rather because of—the looming fiscal austerity caused by the pandemic and post-Brexit economic relationship, both countries should seize the opportunity of the Lancaster House treaties anniversary to relaunch their cooperation in the capability field by focusing on identified NATO and EU capability shortfalls and building on ongoing or recent joint programs. Brexit could complicate this line of effort, but it does not necessarily prohibit it either, with the European Defense Fund allowing association, under certain conditions, of non-EU partners.

  • Be the engines of Europe’s military credibility. France and the United Kingdom are the only two European nations able to raise the operational ambition of Europe. At the bilateral level, they should first ensure that the CJEF reaches its full operational capacity, especially for high-intensity warfare. In order to prevent this force from becoming an empty shell, the two partners should reaffirm their political will to prioritize its deployment in the near term if an opportunity presents itself. Both countries should also explore ways of strengthening the access to their respective military bases with a view to enhancing their joint operational readiness. Building on the lessons drawn from the CJEF, France and the United Kingdom should continue to play leading roles in the development of the UK-led Joint Expeditionary Force (JEF) and French-initiated European Intervention Initiative, an ad hoc framework of 13 European states aimed at increasing the preparedness and coordination between their armies for potential quick military reactions to crisis. Last, the two partners should take the lead in planning the European response to global security challenges, such as the defense of freedom of navigation in the Indo-Pacific.

  • Renew a more robust strategic dialogue on defense and security issues. The political dialogue between the two capitals has been considerably weakened in recent years, mainly due to Brexit. Because only a steady and high-level political monitoring ensures lasting progress in a bilateral relationship, both countries should relaunch their political dialogue, especially through periodic and substantial bilateral summits. France and the United Kingdom should also formalize and better structure their dialogue and cooperation in critical domains, such as intelligence sharing, cyber security, or space. Nevertheless, the Franco-British tête-à-tête is neither sufficient nor satisfactory in the current context.

Brexit must lead Europeans to think about new formats to maintain an essential strategic dialogue with London. As such, the E3 format of France, Germany, and the United Kingdom is a useful framework to preserve coordination between Paris, Berlin, and London on the most sensitive issues, such as the Iranian nuclear program. Without prejudging the outcome of the Brexit negotiations, occasional participation of the British prime minister in European Councils could make sense when the international context requires a unified European position. A similar model is followed by NATO when it occasionally invites the foreign and defense ministers of partner countries Finland and Sweden to its ministerial meetings.

  • Revive trilateral coordination between France, the United Kingdom, and the United States. The complex, networked nature of today’s security challenges demands flexible formats that are less about the institution and more about the effect. Because both the United Kingdom and France have very dense defense and security relationships with the United States, this format would be an opportunity to bridge challenges. As recently proven by Operation Hamilton, when Washington, London, and Paris carried out joint strikes against Syrian government chemical weapons sites in response to the Douma attack in April 2018, all three countries can act swiftly and decisively once their strategic interests are aligned.

Rachel Ellehuus is deputy director and senior fellow with the Europe, Russia, and Eurasia Program at the Center for Strategic and International Studies (CSIS) in Washington, D.C. Pierre Morcos is a visiting fellow with the CSIS Europe, Russia, and Eurasia Program.

Commentary is produced by the Center for Strategic and International Studies (CSIS), a private, tax-exempt institution focusing on international public policy issues. Its research is nonpartisan and nonproprietary. CSIS does not take specific policy positions. Accordingly, all views, positions, and conclusions expressed in this publication should be understood to be solely those of the author(s).

© 2020 by the Center for Strategic and International Studies. All rights reserved.

Rachel Ellehuus

Pierre Morcos