Signed on the 6 April 1963 by UK Prime Minister Harold Macmillan and US President John F Kennedy, the agreement was for the UK to buy the Polaris strategic weapons system from the USA – this was later updated to Trident in 1982. The PSA remains one of the most important intergovernmental agreements in the history of our two nations.
PSA became a pillar of the nuclear special relationship between the UK and the US and formalised the co-operation agreed in the 1962 Nassau Agreement. It was the first of its kind and helped both nations to collaborate and deliver their respective nuclear deterrents.
This commitment has enabled the UK to maintain its Continuous At Sea Deterrent (CASD) since 1969. It guarantees safety for the UK, NATO allies and the US by deterring the most extreme threats to our way of life.
The Polaris Sale Agreement not only maintains CASD, but it’s also helped achieve amazing innovations in technology and science, which is key for the future submarine workforce.
Designing, building, maintaining and operating the deterrent directly supports tens of thousands of jobs and brings investment to communities across the UK. The future holds even greater promises in technological advances, enabling both the UK and US to maintain deterrence.
Through the Dreadnought Alliance, we're proud to be playing our part in this truly incredible national endeavour.
