Lib Dem activists back calls for fewer Trident submarines

Estimates of the cost of like-for-like renewal range from £15bn to twice that figure

The Lib Dem conference has backed calls for a reduction in the number of Trident submarines while still maintaining a UK nuclear capability.

Under Lib Dem proposals, the 60-year-old policy of continuous at-sea patrols would end with submarine numbers cut from four to at most three.

The Lib Dems say it represents a "step down the nuclear ladder" but the Tories say a "part-time deterrent" is wrong.

A decision on Trident has been delayed until after the 2015 election.

The Conservatives back the like-for-like replacement of the UK's nuclear weapons system but the Lib Dems have called for a slimmed-down version to save money and to put an end to what they say is the current outdated "Cold War posture".

Reducing the number of submarines would be the "greatest single act of de-escalation ever undertaken by one of the established nuclear powers", the party's policy document - approved by activists on Tuesday - said.

'Bold and radical'

Ahead of the main vote, party members rejected an amendment calling for the UK's nuclear weapons system to be scrapped by 322 votes to 228.

The man who led a review looking at alternatives to Trident, Chief Secretary to the Treasury Danny Alexander, told the Glasgow conference the party's position was the product of one of "most detailed, thorough, and comprehensive analyses of the options on nuclear available to this country".

"As a party, let's not sit in a position of purity where we can't make a difference, let's choose a policy which we can actually deliver in government," Mr Alexander said.

Former defence minister Nick Harvey said the UK could no longer "wave weapons of mass destruction around" when there was no stated enemy and said that the scaling down of Trident was an "intelligent way forward".

Activists expressed a range of views on the subject of nuclear disarmament and the UK's conventional military capability.

Paul Twigger said scrapping Trident would be a "bold and radical step" and would bring political benefits to the Lib Dems. "It's time to drop the ballast of nuclear weapons and our party will soar," he said.

But Monroe Palmer ridiculed the suggestion that submarines could be sent to sea in future unarmed, their arsenal to be redeployed in periods of increased tension.

"That should scare the living daylights out of the enemy," he told the conference.

George Cunningham said a slimmed-down Trident was not a "workable solution" and warned that the "world has not become a safer place" since the end of the Cold War and there was still a direct nuclear threat to the UK.

The motion also called for a review of arms exports policy, including a presumption that countries on the Foreign Office's list of nations with questionable human rights records should not be traded with.