The end of the Cold War allowed all the nuclear powers to reassess their capability and trim back defence expenditure.

There are now no American nuclear weapons held in Britain.

Under the auspices of the New World Order, the UK is in the process of halving its nuclear stockpile to fewer than 200 warheads. The figure itself is a landmark if, for no other reason, than it is the first time the government has put a precise number on Britain's nuclear weapons.

The government's Strategic Defence Review, announced in 1998, established new cutbacks which are currently being implemented.

 

But while the review noted that "the world would be a better place" if nuclear weapons were not necessary, it found "conditions for complete nuclear disarmament do not yet exist".

However, it did commit to maintaining only the "minimum nuclear deterrence required to deter threats to our vital interests".

Britain's only nuclear deterrent is the submarine-launched Trident missile.

Under the SDR provision, the Royal Navy will operate four Trident ballistic missile submarines, each of which is to carry 48 warheads - half the last government's ceiling of 96.

It means Britain will hold fewer than 200 nuclear warheads.

Currently three Trident submarines are operational. A fourth, HMS Vengeance, began service in 2000.

The subs, based at Faslane in Scotland, maintain a continuous operation, with at least one on patrol at any time.

They will be on a reduced state of alert - their missiles "detargeted" and on several days "notice to fire", rather than the minutes notice during the Cold War.

The Ministry of Defence has also said it will reduce holdings of fissile materials for use in nuclear weapons. Fissile materials are those capable of undergoing nuclear fission which could then be used to make a warhead.

The Economist newspaper has called the SDR cutbacks an "adroit but cautious move towards nuclear disarmament".

Certainly, the MoD claims it will leave Britain with nuclear holdings "considerably lower" than any other member of the UN security council's permanent five.

However, it has also been pointed out that Trident missiles carry far greater targeting accuracy than the Chevaline warheads on the old Polaris fleet.