Hartmut Bühl / Nannette Cazaubon – European News Journal, Paris
A “truly historic” nuclear agreement, as British Prime Minister Keir Starmer called it, was announced in Northwood on 10 July 2025, at the end of the three-day visit of French President Emmanuel Macron to London.
In response to the Russian threat on the European continent and the uncertainty over their American ally, the two heads of state reaffirmed their “long-standing and determined commitment to nuclear cooperation” in a joint statement.
“There is no greater demonstration of the strength and importance of our bilateral relationship than our willingness to work together in this most sensitive area.“ France-UK declaration of 10 July 2025
Two nuclear forces but not the same story
To understand this “historic” moment, let’s recall the difference between the two nuclear powers. The French nuclear arsenal is completely independent in terms of production, operation, decision-making, and commissioning – a point to which President Charles de Gaulle, who initiated the independent French nuclear programme in the 1960s, attached major importance, as his obsession was to limit American influence in Europe.
For the British nuclear arsenal, the opposite is true: it is subject to the 1962 Nassau (Bahamas) agreement. The United States committed to supplying Polaris medium-range missiles for British submarines, which provided the United Kingdom with a modern deterrent. However, the agreement also stipulated that these missiles would be assigned to NATO, except when “supreme national interests” were at stake.
This effectively meant that London was renouncing an independent nuclear force and remaining largely dependent on the United States for the acquisition and maintenance of its nuclear weapons. A furious de Gaulle vetoed British membership of the European Economic Community (ECC) in 1963.
A new perspective for Europe’s security
While nuclear deterrence for Europe has so far come primarily from the United States, the Northwood agreement suggests additional nuclear protection for the European continent at a time when the US ally under Trump’s lead has become far less reliable.
At present, the agreement is primarily of political importance. And that is precisely the purpose of deterrence: to prevent a hostile nuclear strike by signaling the enemy’s destruction through an immediate nuclear response. The nuclear weapons arsenals of both partners serve solely for deterrence and are not applicable to operations on land or at sea.
In practice, France and the UK will retain their own decision-making processes and strategic ambiguity. And the UK would not be able to shake off its dependence on the US in one fell swoop.
However, as a first step in this new coordination, it was decided to create a Franco-British Nuclear Steering Group, led by the French Presidency and the UK Cabinet Office, to provide political direction for this work. “The decision is that we don’t exclude the coordination of our respective deterrents. It’s a message that our partners and adversaries must hear,” Macron said.
“The decision is that we don’t exclude the coordination of our respective deterrents. It’s a message that our partners and adversaries must hear. ” Emmanuel Macron
Finally, let us point out that Europe is expressly mentioned in Northwood’s statement: “France and the United Kingdom agree that there is no extreme threat to Europe that would not prompt a response by our two nations.” This means nothing less than Europe being considered an integral part of the common security interests of both countries.
It confirms that, despite Brexit, the United Kingdom is finally ready to engage in European defence matters. This is also a clear message for the owner of the White House in Washington.
We can image that de Gaulle would have applauded.
