Amid signs of a widening Cabinet split, the Foreign Secretary, Hilary Benn and Peter Hain have all expressed private reservations about extending or replacing the Trident missile system and a lack of consultation with the wider Labour Party.

The Cabinet is to have its first discussion tomorrow on the subject, although one source described this as a “first run round the issues”. A bigger, final Cabinet debate and conclusion should follow just before the publication of a White Paper setting out the Government’s recommended option in mid-December.

The most likely outcome is to extend the lifespan of the existing fleet of four Vanguard submarines and D5 Trident missiles rather than buy a replacement system from the United States or commission a completely new package. Both would be more expensive.

MPs are to be offered a vote as well as a Commons debate early next year, in response to a growing clamour from Labour backbenchers, but only on the principle of retaining a nuclear deterrent and not on the individual options.

Allowing MPs a vote is seen only as of symbolic importance, as the Conservatives would almost certainly vote with the Government to keep Britain as a nuclear power, thus cancelling out any rebellion by anti-nuclear left-wing Labour MPs.

But first Tony Blair must navigate differences of view within the Cabinet on an issue that threatened to split the Labour Party a generation ago and remains sensitive, even though he and Gordon Brown have both already committed themselves to another generation with Britain as a nuclear power.

A government source told The Times: “There are three people in the Cabinet with concerns: Margaret, Hilary and Peter. They will have said something internally.”

Mrs Beckett’s view is the most important as, technically, the Cabinet’s decision would be taken on her recommendation as Foreign Secretary, made jointly with Des Browne, the Defence Secretary. The White Paper will be produced jointly by the Foreign and Commonwealth Office and Ministry of Defence.

Mrs Beckett, whose roots are on Labour’s Left, hinted at reservations last month when she accepted that some people would question whether to continue with Trident or not, despite Labour’s non-specific manifesto pledge to maintain an independent deterrent. “The nature and shape of the nuclear deterrent we have and are maintaining and keeping up to date was dictated in the Cold War circumstances of decades ago. The security situation today across the world is very, very different,” she told The Sunday Times.

Peter Hain, the Wales and Northern Ireland Secretary and candidate for the Labour deputy leadership, also voiced public concerns last weekend, telling the BBC One Politics Show that party members must be involved and not have a decision handed down “from on high”.

Four options are understood to be on the table: not replacing Trident, amounting to uni- lateral disarmament; extending the lifespan of existing Vanguard submarines and Trident D5 missiles beyond 2024; buying a new replacement-system Trident under agreement with the United States; or breaking away from the US to commission a state-of-the-art system of a different kind.

Owing to the delicacy of the issue, The Times has been told that no Cabinet papers have been circulated to ministers, as would normally happen before an imminent discussion.

The Roman Catholic bishops of England and Wales issued a statement yesterday calling on the Government not to replace Britain’s nuclear deterrent, saying the country was at a “moral and strategic crossroads”.

Missile facts

£12.57bn
Estimated acquisition cost of Trident nine years ago

4,000
Range in nautical miles of submarine-launched Trident II D5 missiles

12
Number of warheads each missile carries

38
Years the Royal Navy has operated always-at-sea patrols, first with Polaris

Source: Ministry of Defence

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