Tony Blair's statement in full

Michael Evans Q&A: Trident explained

Graphic: Britain's nuclear deterrent

Work on designing a new generation of nuclear submarines to maintain Britain’s independent deterrent will get under way next spring, possibly even before Tony Blair leaves office and thanks to the backing of David Cameron.

In spite of a certain rebellion by up to 80 Labour MPs, Mr Blair was assured last night of the legacy of a replacement for Trident after the Tories promised full support for his plans.

Mr Blair told the Commons that it would be “unwise and dangerous” for Britain, alone of the nuclear powers, to give up its deterrent. Despite Britain’s close co-operation with America, the deterrent had to be independent in case there were circumstances in which Britain was threatened and the US was not, he said.

Up to £20 billion will be spent on a new system, less than expected. This is mainly because the number of warheads will be reduced from 200 to 160 and the number of submarines could be cut from four to three if the newly designed vessels could be shown to maintain continuous patrol at a lower figure. In addition, the life of the existing 50 D5 Trident missiles will be extended to 2042 and the new weapons will be designed in collaboration with the United States.

This will keep Britain as a member of the nuclear club until at least the 2050s. Running the new submarines will cost more than £1 billion a year.

Mr Cameron told Mr Blair that the Government would have Tory support if it decided that a fourth submarine was necessary and if he kept the same number of warheads as now.

The Commons will vote in March on renewing Trident, after which work on designing the new submarines will be commissioned. Construction will go to British industry, with thousands of jobs involved.

Mr Blair said that although the Cold War was over no one could be certain that a big nuclear threat to Britain’s strategic interests would not emerge. There was a new threat from states such as North Korea or Iran. “The risk of giving up something that has been one of the mainstays of our security since the war, and doing so when the one certain thing about our world today is its uncertainty, is not a risk I feel we can responsibly take,” he said.

Mr Blair insisted that the system was fully independent and that a missile could be fired only on the instructions of the British Prime Minister. He said that Britain had the smallest arsenal of nuclear warheads among the recognised nuclear-weapons states and was the only one to maintain only a single system.

The decision exposed deep divisions on the Labour benches. The former minister Michael Meacher said that it would “severely restrict” spending on conventional defence systems, climate change and long-term energy and security issues.

Sir Menzies Campbell, the Liberal Democrat leader, insisted that decisions did not have to be taken until the next decade, and accused Mr Blair of seeking to secure a legacy.

The White Paper, The Future of the United Kingdom’s Nuclear Deterrent, published jointly by the Ministry of Defence and the Foreign Office, dismissed the notion that Britain was missing out on setting an example to would-be nuclear weapons states by not giving up its deterrent.

“There is no evidence or likelihood that others would follow the UK down a unilateralist route,” the document said.

The number of new enhanced Trident D5 missiles to be bought from the United States is not known but the current stockpile is 50. These are taken from missiles stored at the US Navy base at King’s Bay, Georgia. This pooling arrangement would continue, defence sources said.

BAE Systems, which built the four Vanguard submarines at Barrow, welcomed the decision. It employs 3,000 people at Barrow, but there are thousands of other jobs involved: at the Atomic Weapons Establishment at Aldermaston in Berkshire, the Rolls-Royce facility at Derby and the nuclear submarine refit yard at Devonport.

The deterrent

1980
Trident 1 (C4) ordered

1982
Trident 11 (D5) ordered

1986
HMS Vanguard ordered

1987
HMS Victorious ordered

1990
HMS Vigilant ordered

1992
HMS Vengeance orderd

1994
First Trident patrol with HMS Vanguard

2007
300th UK submarine deterrent patrol

2020s
First new Trident patrol

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