As part of the agreement, London and Paris will co-ordinate policies and more closely align their nuclear doctrines, while each retains control of its own arsenal.<\/p>\n
\u201cThere is no greater demonstration of the strength and importance of our bilateral relationship than our willingness to work together in this most sensitive area,\u201d reads the joint UK-France statement on the declaration.<\/p>\n
\u201cOur adversaries will know that any extreme threat to this continent would prompt a response from our two nations,\u201d Starmer said standing next to Macron at the British military headquarters in Northwood, north-west London.<\/p>\n
\u201cIt\u2019s a message that our partners and adversaries must hear,\u201d said Macron, who was wrapping a three-day state visit to the UK.<\/p>\n
![\"France's](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/07\/SEI_258554966.jpg\")
Macron and Starmer being briefed by a Nato official at a military base in north-west London this week (Photo: Ludovic Marin\/AFP)<\/p>\n
The agreement, called the Northwood Declaration, is the most significant revision of the doctrine between Britain and France since 1995, when prime minister John Major and French president Jacques Chirac agreed to deepen nuclear co-operation.<\/p>\n
It comes as Russia <\/a>is escalating its aggression, and the United States appears to be retreating <\/a>from its traditional level of engagement with European allies. Europe needs to \u201cstep up\u201d and do more for its \u201ccollective defence\u201d, Starmer said.<\/p>\n Although a member of Nato<\/a>, France has traditionally kept its nuclear weapons under national control, separate from Nato\u2019s integrated military command. This means that France decides independently how and when to use its nuclear arsenal \u2013 a concept called \u201cstrategic autonomy\u201d.<\/p>\n The UK\u2019s nuclear weapons are more closely tied to the alliance\u2019s collective defence strategy. Britain\u2019s nuclear force is often described as a \u201ccontribution to Nato\u2019s deterrent\u201d, meaning it helps deter attacks on all Nato members.<\/p>\n Currently, Russia has the largest stockpile of nuclear warheads in the world, estimated at approximately 5,580 \u2013 with around 4,380 of them operational, according to the Federation of American Scientists. But only 1,710 are \u201cdeployed\u201d, or ready for use.<\/p>\n But it is dramatically outstripped by the collective military capabilities held by Nato 32 member countries \u2013 particularly as the US is the alliance\u2019s primary nuclear guarantor, with its arsenal deployed across Europe under shared defence arrangements.<\/p>\n France is also a nuclear power but it currently does not use its nuclear capabilities for Nato-wide defence. <\/p>\n France\u2019s nuclear capability has been seen as complementary to Nato\u2019s deterrence, reinforcing the alliance\u2019s broader strategic posture. But this deal with the UK could mean more formal alignment.<\/p>\n A nuclear steering group will be established \u201cto provide political direction\u201d for the UK-France pact, led by the French presidency and the UK Cabinet Office to co-ordinate \u201cnuclear policy, capabilities and operations\u201d.<\/p>\n The US State Department assessed in 2024 that the Russian military possesses between 1,000 and 2,000 nuclear warheads for non-strategic systems, while non-governmental organisations estimate approximately 1,550 warheads for these weapons.<\/p>\n The US has deployed a similar number of nuclear warheads, with the total estimated to be approximately 1,770.<\/p>\n The British and French nuclear arsenals are considerably smaller. <\/p>\n The United Kingdom has a total stockpile of 225 warheads, with 120 deployed, according to the Federation of American Scientists. France possesses 290 warheads, of which approximately 280 are operationally deployed.<\/p>\n \u201cOur nuclear forces are independent, but can be co-ordinated and contribute significantly to the overall security of the alliance, and to the peace and stability of the Euro-Atlantic area,\u201d the two countries said in the joint statement.<\/p>\n In addition to the renewed nuclear agreement and revamped joint force, France and Britain have also committed to restocking their supplies of Storm Shadow missiles<\/a>.<\/p>\n![\"\"](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/07\/SEI_241820950_53b03e.jpg\")
Nato\u2019s nuclear arsenal vs Russia\u2019s <\/p>\n![\"British](\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/07\/SEI_258553785.jpg\")
Starmer and Macron at a maritime command centre in London (Photo: Leon Neal\/AP)<\/p>\n