Britain is to maintain its nuclear defence with a straight submarine-based replacement for the Trident missile system, The Times has learnt.

The plan is favoured by Gordon Brown, Tony Blair and most of the Cabinet. But in a move that has big implications for the cost, Mr Brown believes that detailed decisions about the number of warheads each submarine would carry, and their range, can be made at a later date.

The Chancellor is understood to be in favour of making the decision about the principle of replacement as soon as possible so that the building of the submarines can be ordered and workforces kept on. But by deferring decisions there would be an additional means for controlling costs, a move favoured by many other ministers.

MPs will vote on the Government’s recommmendation in February. Those who want to give up the independent deterrent, or would prefer merely to extend the life of the existing Vanguard system, will be able to vote against it. However, the Commons seems certain to back a replacement, with Conservative MPs falling in behind the Government.

Yesterday’s Cabinet meeting decided that a White Paper setting out the options for replacing Trident will be published next month. There will be then be a three-month consultation period to explain to the public and the Labour Party the thinking behind them, and to hear their reactions.

Ministers such as Margaret Beckett and Peter Hain, who have been worried about the appearance of the Cabinet taking its decision on Trident without explaining it to the country, were happy last night about the decision to have a lengthy consultation period. Mr Brown strongly backed that move.

But among senior ministers there is understood to be a clear majority in favour of going for a new system because the Cabinet will discuss the issue again early next month.

Alternative plans for an air-delivery missile system and a land-based system have been dropped, even though Geoff Hoon, the Europe Minister and former Defence Secretary, argued again in the Cabinet yesterday that they should be considered. Mr Hoon had pressed for their examination while at the Ministry of Defence but when he was replaced by John Reid the submarine-based system again won favour.

Most ministers hope that the decision can now be dealt with before Mr Blair goes.

No one at yesterday’s meeting argued that the deterrent should be given up. Mr Hain, who allowed his membership of CND to lapse two years ago, said that Labour had been punished heavily in the past when it had fought on a unilateralist manifesto. But Patricia Hewitt, the Health Secretary, was among several spending ministers who argued that, although there should be a new system, the costs should be kept down so that other priorities were not damaged.

Mr Hain told The Times yesterday he was delighted that there would be a proper period of consultation and that Parliament would make a decision.

“I was elected on a platform of maintaining the deterrent and I remember only too well what a terrible period we had when we were in favour as a party of unilateralism. I am not in favour of revisiting that issue.”

Nuclear count

Approximate number of nuclear warheads for the biggest nuclear nations

7,339
United States

7,200
Russia

192
Britain

109
France

100-200
China

Source: Nuclear weapons archive

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