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November 2018

The UK-France Defence
and Security Relationship:
How to Improve Cooperation

<p><span style=The UK-France Defence
and Security Relationship:
How to Improve Cooperation


The opinions expressed in this report do not bind these persons or the institutions of which they are members

  • Lord Robertson, former NATO Secretary General (chair UK delegation)
  • Bernard Cazeneuve, former Prime Minister (chair French delegation)
  • Patricia Adam, former President of the French National Assembly’s Committee on National Defence and Armed Forces
  • Nicolas Baverez, Partner, Gibson, Dunn & Crutcher LLP
  • General Sir Adrian Bradshaw, former NATO Deputy Supreme Allied Commander Europe
  • Nick Butler, Visiting Professor, King’s College London
  • Patrick Calvar, former Chief of the General Directorate for Internal Security, Special Advisor at Montaigne Institute
  • Matthias Fekl, former Minister of the Interior
  • Professor Sir Lawrence Freedman, Emeritus Professor of War Studies, King’s College London
  • Ian King, former CEO, BAE Systems
  • Alain Le Roy, Diplomat and former Secretary General of the European External Action Service
  • Marwan Lahoud, Partner, Tikehau Capital, former CEO, MBDA
  • Dominique Moïsi, Special Advisor, Institut Montaigne
  • Benoît Puga, Grand Chancellor of the Légion d’Honneur and former Chief of the Special Military Staff of the President of the French Republic
  • Lord Ricketts, former Ambassador to Paris, former National Security Advisor


"A fragile or fractured relationship between the United Kingdom and France would jeopardise our security and that of other countries in Europe and around the world.  As necessary as it is, however, this cooperation has never been so precarious. In response to this urgency, we are jointly formulating concrete proposals to give new impetus to this historic partnership based on shared values and ambitions."
Bernard Cazeneuve, former Prime Minister and 
Lord Robertson, former NATO Secretary General, 
the two chairs of the working group.



Damn English! Bloody Frenchies! Although relations between France and the United Kingdom have not always been good, over time our ties have evolved into a lasting friendship and a strong alliance, particularly in the field of defence and security.

Since the Entente Cordiale of 1904, cooperation between France and the United Kingdom has gradually strengthened to finally take the form of bilateral agreements in the operational, capability and nuclear fields (Saint-Malo Declaration in 1998, Lancaster House Treaties in 2010).  In recent decades, our two countries have chosen to fight side by side on several occasions: in Kosovo in 1999, in Libya in 2011, in Syria with the joint strikes with the United States in recent months, etc.

But this alliance is now weakened. Old threats are resurfacing, while new ones are emerging: terrorism, geopolitical imbalances, cybersecurity, the return of "empires", and of course Brexit.  

Yet this cooperation is essential for both our countries, and beyond, to ensure European and global security. 

Seized by this reality, the Franco-British working group, convened by Institut Montaigne and the Policy Institute at King’s College London, under the chairmanship of Bernard Cazeneuve and Lord Robertson, is publishing today a report that aims to give a new dynamic to our cooperation. 

In it, they formulate a series of strategic proposals for the leaders of both countries to ensure that Brexit does not jeopardize our collective security, while providing their armies with the military capabilities necessary to win the wars of tomorrow together and strengthen their international influence.

Why is Franco-British cooperation so important?

France and the United Kingdom are two similar geopolitical powers...

The UK-France Defence and Security Relationship: How to Improve Cooperation

sources : IISS - The Military Balance / Eurostat - General government expenditure by function / SIPRI - world nuclear forces

In Europe, France and the United Kingdom are comparable in many respects:

  • Their operational capabilities: they are the two largest armies on the continent in terms of manpower.
  • Their nuclear power: they are the only two countries on the continent with nuclear weapons and each has made deterrence one of the foundations of its sovereignty doctrine.
  • Their projection forces: they are the only armies capable of projecting themselves alone into external theatres of operations.
  • Their diplomatic role: they are the only two permanent members of the United Nations Security Council.
  • Their investments: together they account for nearly half of defence spending in Europe with $105 billion invested in 2016;
  • Their defence industries: they are dynamic, pioneering and prosperous.
  • Their membership in the Atlantic Alliance (NATO).

... facing common threats

In 1995, at a joint conference, President Jacques Chirac and Prime Minister John Major stated that neither country could "imagine a situation in which the vital interests of either of [their] two nations, France and the United Kingdom, could be threatened without the vital interests of the other also being threatened." 

Today, in an uncertain geopolitical context, France and the United Kingdom must face together:

  • The threat of Islamist terrorism

In 2017, there were five terrorist attacks in France and five in the United Kingdom. In addition, they are the two countries with the highest number of nationals having joined the Islamic State in Iraq and Syria (850 British nationals and 1,100 French nationals). The fall of this terrorist organization does not reduce its dangerousness. The many fighters who have returned from Syria and Iraq and have since been imprisoned in the United Kingdom, France and various European countries pose a real threat..

  • To Russia's aggressive foreign policy

Russia's annexation of Crimea in 2014 revived expansionist policies and, in response, levels of military alert that the world had not experienced since the Cold War. Through its military exercises on NATO's eastern borders, Russia poses a clear threat to the European geopolitical balance.

Russian interference in democratic processes in recent years (Brexit and the 2017 presidential election) has demonstrated certain vulnerabilities in national computer networks and has tested the resilience of our societies, making them aware of the need to develop offensive and defensive cyber capabilities. 

Finally, Russian secret operations are just as problematic, for example the poisoning of former Russian spy Sergei Skripal in London.

  • Security challenges caused by instability in the Middle East 

The current instability in the Middle East and the regional expansion of Iranian influence are also major security challenges. Such instability, combined with the Syrian conflict, led to the 2015 migration crisis with the arrival of more than 1.5 million refugees in Europe, creating political instability within the EU and reinforcing populist rhetoric. 

  • The rise of China

China's rise to power is certainly a strategic challenge for both our countries. It requires long-term investments, particularly in foreign policy and counter-intelligence.

China's military apparatus is rapidly modernizing and its military capabilities are increasing at an equally rapid pace. In addition, China is becoming a major strategic player in Asia, but also in more remote regions of the world, particularly in Africa.

Franco-British cooperation: where do we stand?

Cooperation in defence and security matters is one of the essential characteristics of relations between the United Kingdom and France: the Treaty of Dunkirk in 1947, the military alliance of the Western European Union in 1948, the Joint Nuclear Commission in 1992, the Franco-British European Air Group in 1994, the Saint-Malo Declaration in 1998, etc.

In the field of defence

The Lancaster House Treaties signed on 2 November 2010 are a symbol of deeper and more intense cooperation between our two countries. They are structured around three pillars: 

The UK-France Defence and Security Relationship: How to Improve Cooperation
  • Operational, with the development of the Combined Joint Expeditionary Force (CJEF)

On the occasion of the Lancaster House agreements, France and the United Kingdom decided to establish a joint expeditionary force in order to be able to intervene jointly in high-intensity operations and to enter the field first. In recent years, the French and British armies, whether navy, army or air force, have worked hard to achieve an almost perfect level of interoperability. To date, this joint expeditionary force has not been deployed in any theatre of operations. 

  • Industrial, by promoting cooperation between defence industries

The Lancaster House agreements have made industrial cooperation a priority in order to develop joint armament programmes and allow economies of scale for armament equipment. MBDA, a Franco-British company specialising in missiles, is undoubtedly one of the greatest successes in this field. With this undertaking, our two countries have reached a significant level of interdependence, a sign of the trust and friendship they share.

In terms of capabilities, the Lancaster House Treaties have resulted in the definition of three major joint projects aimed at developing "high spectrum" capabilities: a future air combat system programme, the Future Combat Air System (FCAS); a stealth supersonic cruise missile programme (FCASW/FMAN-FMC); and a maritime anti-mine programme, the Maritime Mine Counter Measure (MMCM). 

These programmes are at different stages of development, and there is no guarantee that they will all be successful.

  • Nuclear, finally, by a separate treaty providing for technological cooperation

To ensure that both countries maintain an autonomous and technologically advanced nuclear deterrent, our two countries have decided to cooperate in this sensitive sector and have undertaken to build a joint nuclear simulation centre in France and a joint nuclear research centre in the United Kingdom. This is one of the most successful areas of cooperation between our two countries.

In terms of security

With regard to security, cooperation is more informal or takes place through certain European mechanisms. It is possible to distinguish three types of cooperation:

  • Between police forces

The two countries have set up different police systems without this preventing fruitful cooperation. Whether it is drug trafficking, organised crime, illegal immigration or any other area, this cooperation is mainly carried out through European mechanisms.

  • Between judicial institutions

There is bilateral cooperation, particularly on border issues. The considerable traffic between the two countries is regulated by the 2003 Le Touquet Treaty, which creates a legal basis for juxtaposed controls in Calais, Coquelles, Dunkirk, Paris, Brussels, Lille and Calais-Fréthun.

  • Between the intelligence services

Intelligence is a key element of cooperation between the two countries. Given its importance in terms of sovereignty, this cooperation is informal and essentially takes place outside the Community framework, although some European databases are used, in particular the PNR.

What challenges do we face to strengthen this cooperation?

Significant differences of opinion

While the United Kingdom and France share common values and a common vision, their appreciation of their role in the world can sometimes diverge.

Franco-British cooperation can be limited by divergent geopolitical cultures and ambitions. Thus, for the United Kingdom, the main alliance remains the one established with the United States and the privileged framework for cooperation is that of NATO. 

For its part, France considers European integration a priority and traditionally wishes to strengthen the Franco-German couple. Moreover, Paris's support for the EU's concept of strategic autonomy may also represent a limit to NATO's strengthening in Europe. 

For France, it could be difficult to reconcile its alliance with the United Kingdom with its important European ambitions. As for the United Kingdom, its role in the world could also be called into question by Brexit. Will she distance herself from continental Europe in an attempt to give substance to her theory of "Global Britain"?

The need to reorganize security cooperation

Some European mechanisms and institutions, such as Europol, the SIS II database or the European arrest warrant, have been created by the EU and fall under European law. The participation of a third country in the EU in these instruments is therefore not theoretically provided for by the European treaties. 

Finally, a crucial issue remains the jurisdiction of the European Court of Justice (ECJ) in the United Kingdom. While it was initially a red line in the negotiations, Theresa May has since softened her position by indicating that she accepts her jurisdiction under certain conditions.

Our proposals to strengthen Franco-British cooperation in defence and security matters

The future of Franco-British cooperation is precious but has never been so precarious in the face of the emergence of new threats, American isolationism and Brexit.

Tackle the security challenges raised by Brexit
In detail

Proposal 1: Ensure that Brexit does not endanger security cooperation between the UK and the EU27

Defence and security cooperation between the UK and the EU27 is of tremendous importance for both countries: Brexit must not jeopardise it, and defence and security must not be used as a leverage in the negotiations. 

Security issues need to be isolated and insulated from the rest of the Brexit negotiations. Both the UK and the EU27 need to separate defence and security from the trade and customs parts of the Brexit negotiations, in recognition of the shared benefits of UK-EU cooperation in this area. 

The UK has already proposed a specific treaty on security, in which it suggests going further than the current agreements in place with other foreign countries. The EU27 do not want to create a specific status for the UK that might disturb relationships with other third countries, yet it seems possible to find agreements that would make it a privileged partner. 

Such an agreement might open up to third countries several defence and security mechanisms that are currently reserved to member states, such as SIS II; we also need to update the third-party status in the agreement to ensure closer association is possible. It would also require establishing consultation processes, finding the right balance between two legitimate objectives: the UK’s desire to participate in military operations only if it has been involved in planning them, and the EU’s desire to maintain autonomy in decision-making.

Proposal 2: Maintain border cooperation agreements

After Brexit, the UK will no longer be part of the EU, which might endanger the border cooperation agreements set up by the Treaty of Le Touquet and the Sangatte Protocol.

We believe it is imperative to maintain these agreements. The UK and France cannot allow these agreements to be influenced by withdrawal negotiations and future security arrangements between the UK and the EU27. The UK government should consider how it might take on a greater proportion of burden-sharing from France.

Ensure the full implementation of the Lancaster House Treaties
In detail

Proposal 3: Reinforce strategic dialogue and mutual knowledge

Ultimately, defence and security cooperation depends less on the language of treaties and declarations than on the signatory country’s leaders. Political will has enabled us to overcome difficulties on the implementation of some aspects of the Lancaster House Treaties, but when political will has been lacking, implementation of other aspects has failed.
The creation of a biannual bilateral head of governments’ summit in the Lancaster House framework was, in this way, very useful. But it appears that we need to go further, even more so as an implication of Brexit is that British leaders will no longer attend European Council and other high-level meetings, thereby reducing opportunities for interactions with French leaders.

Thus, we advocate for the creation of an annual UK-France Defence and Security Council, larger than the council between the Defence Ministers that was set up by the 2018 Sandhurst summit. It should involve the President, Prime minister, Foreign Secretaries, Defence Ministers, Home Secretaries and Chiefs of Defence Staff, and intelligence chiefs. 

This council would be complemented by a more regular "2+2" dialogue, consisting of Foreign Secretaries and Defence Ministers, and an established ‘quint’ dialogue between the heads of the main intelligence services, as during the 2018 Sandhurst summit.

Proposal 4: Prepare the CJEF for operations

While the CJEF concept has been praised and tested successfully during training, it has not yet been deployed operationally.

The first objective should be to ensure its full operational capability, planned for 2020. The main task of the CJEF is to set a framework for joint UK-France operations to be possible at appropriate notice and with the right capabilities. 

Joint engagement can already be achieved on air and sea issues, because existing systems are largely interoperable and allow for efficient deployment in these environments. More work remains to be done to build interoperability in land environments. The anti-submarine challenge seems an especially decisive area of joint intervention in cooperation with the US.

Last but not least, since it has always been clear that CJEF should in due time examine the conditions for a possible opening up to other allies, it would be useful to start working on its plugging in with NATO and the emerging European Intervention Initiative: it would be a good way for the UK to signal that it remains committed to European defence, a way for the European Intervention Initiative to rest on a strong and tested framework and to integrate the two main military powers of the European continent.

Proposal 5: Increase cooperation through training facilities and maintenance

France and the UK should increasingly rely on each other for training facilities and equipment maintenance, thus maximising their use and minimising the cost to both countries. Moves towards cooperation on servicing, maintenance and training in areas where both countries hold the same equipment, such as the C-130 and the A400M aircrafts, should offer opportunities for financial savings, thereby releasing funding for investment in other areas of defence. There may also be scope to utilise the British Army’s training facility in Suffield, Canada for joint UK-France exercises.

Preparing for the future
In detail

Proposal 6: Pursue the objective of building FCAS capacity

Enhanced aerial combat capacities will be crucial for the wars of tomorrow. Yet no European country currently has the financial or industrial capability to build a next-generation aircraft alone, given the investment it requires and the stretching of military budgets. As a result, the risk is losing this competence with the end of the Rafale, Typhoon and Eurofighter programmes. On top of industrial issues, within the context of a loosening transatlantic relationship, it is key for national security to maintain European capability to design autonomous combat air systems. 

The UK’s commitment to purchase 138 F-35 jets (48 have already been ordered, four have been delivered), the absence of current operational need for an FCAS programme on the British side, and the UK’s strong defence industrial relationship with the US, has raised doubts over the completion of the original UK-France FCAS programme, which is important to develop specific technologies that would be needed for the next generation of fighter aircraft.

However, it would be a pity to abandon a programme in which significant financial investments have been made, as a feasibility study and technological work have already begun. Furthermore, the UK has unique capabilities among European states in fighter jet design, whether it is military engines, electronic warfare, sensors or stealth technologies. Plus, the involvement of its air force in high-intensity combat operations and kinetic strikes would help design a combat air system with adapted operational capabilities. By contrast, there are significant differences between the French and the German (mostly defensive) use of air force, that could lead to divergences among programme’s priorities.  

It therefore seems desirable to proceed, in the medium-term at least, with the UK-France FCAS programme, in order to develop the key technologies needed for a future combat air system; and, in the long-term, to merge this programme with the France-Germany FCAS programme as a France-UK-Germany project. In time, this programme might serve as one of the first building blocks of a "combat aircraft MBDA".

Proposal 7: Increase cyber security cooperation by developing formalised and structured modes of cooperation

The UK’s involvement in the Five Eyes community remains a sticking point for France-UK cooperation in cyber security.

However, US-UK cooperation on nuclear issues did not prevent UK-France nuclear cooperation from becoming a pillar of the Lancaster House agreements. That cyber security is a sensitive subject should not prevent stronger French-British cooperation in this area, which is becoming as central as nuclear in strategic affairs.  

We propose going further than the strategic dialogue on cyber threats set up by the Sandhurst summit – instead, complementing the Lancaster House Treaties with a cyber security pillar. This should include the joint development of a doctrine for responding to cyber threats, the development of joint capabilities (especially on the key technologies identified by the French cyber defence strategic review, namely data encryption, detecting and identifying cyber-attacks and AI), and establishing a joint government taskforce to explore options for further cooperation. One of the purposes of this taskforce would also be to formalise cyber cooperation and provide a platform for regular and structured discussions on these issues between the UK and France.

This cyber security pillar can only work under exclusivity and non-disclosure agreements, which would preserve secrecy on jointly developed capabilities.

Proposal 8: Formulate a joint strategic vision to inform R&D planning

All of the joint R&D UK-France programmes designed to prepare for oncoming threats will rely on a common set of key technologies, drawing mainly on AI, cyber security, robotics, stealth and spatial observation. In addition to industrial cooperation, research will be needed to militarise technologies developed by the civil sector.

Although states prefer to develop several capacities alone, there is a clear case to be made for more joint research that is defence and security-oriented. It was an ambition established at the bilateral 2012 Paris summit, but both countries have as yet failed to deliver.

To orientate UK-France defence and security cooperation towards the future, it is necessary to formulate a strategic vision, based on a joint identification of key technologies and potential opportunities. This, in turn, needs to be implemented through a range of bilateral instruments, building on the Sandhurst agreement to develop joint research in AI and cyber security. If the final Brexit agreement allows for the UK to retain some level of access to Horizon 2020 and the European Defence Fund, they could provide sources of funding for joint projects.

Proposal 9: Implement a formal intelligence framework between France and the UK

Nowadays, intelligence cooperation between France and the UK, while regular and deep, works mostly on an informal basis, founded on trust and personal contacts. Although these are imperative, they are not a substitute for more structured, formal relations that are enshrined in law and help to foster intimacy between the two countries. Such a framework is all the more important considering intelligence cooperation is increasingly based on the exchange of data.

The Lancaster House treaties should therefore be complemented by a discreet agreement on intelligence sharing which facilitates cooperation between the UK and France.

Proposal 10: Deepen joint defence engagement activities

Design and implement joint defence engagement activities. As a token of the close relationship between the two countries, joint defence engagement activities should be developed. Through the use and deployment of liaison officers in each countries’ respective defence and foreign affairs ministries, the UK and France can collaborate on outward-facing activities. Such activities might involve, for example, giving joint information briefings to foreign service staff.

Proposal 11: Use and strengthen officer exchange programmes

Exchange programmes have played a key role in facilitating UK-France defence and security cooperation, helping each country to develop a better understanding of the other’s activities and structures, as well as expanding their networks. This mutual understanding should be cultivated further, in order to safeguard cooperation between France and the UK for future generations of military and civilian officers.

<p><span style="color:#ffffff;"><strong>The UK-France Defence<br />
and Security Relationship:<br />
How to Improve Cooperation</strong></span></p>
(50 pages)
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