After a visit to Aldermaston a few years ago, I noted that “no, the United Kingdom does not in any way, shape, or form have an independent nuclear deterrent.”
In 2009, then-UK PM Gordon Brown announced the UK would be willing to consider reducing the number of Trident submarines from four to three.
This came as a surprise to HMG (Her Majesty’s Government), according to a leaked cable from the US Embassy in London, which contained this helpful explanatory note: “The UK Trident system consists of 160 operational nuclear warheads carried by Trident II (D5) ballistic missiles aboard four Vanguard-class nuclear powered ballistic missile submarines. The warheads and submarines are British built, but with substantial American design assistance.”
Emphasis mine.
Update | 9:00 11 December 2010 That phrase appears in two cables, one from 24 July 2009 and another from 24 September 2009. It is, it appears, boilerplate. (The links are to the full text of the cables.)