TRIDENT should be removed from the Clyde within “three or four years” of Scotland voting for independence, SNP policy chiefs are to be told by the party’s influential CND group. It is the first time a specific timescale has been suggested by the internal body.

The removal of nuclear weapons from the Clyde is expected to be a key ambition for an independent Scotland, with many Scots giving the removal of nuclear weapons the reason why they back independence.

However, until now no definite deadline for the process to be complete has been discussed by the SNP.

At its spring conference this year party members voted for a resolution to agree the process should be done “speedily”.

But yesterday Bill Ramsay, convener of the SNP’s influential CND group, told the Sunday National: “From the day of a Yes vote, it should be a three or four year period.

‘‘We will be making a presentation to the SNP’s policy committee in due course and will be putting this timescale to them.”

He said discussions to remove Trident should begin with the UK Government in the weeks after the successful independence referendum and during the “year or two” mark following the vote during which preparations would take place for Scotland to become a sovereign state.

Formal negotiations on removing Trident would not start until the start of the first independent Scottish Government, he added.

Last week Trevor Royle, a respected military historian and author, suggested that following independence the Scottish Government could lease out Faslane to Nato to raise £1.1 billion a year providing funding for schools and hospitals and other public services.

Royle, a fellow of the Royal Society of Edinburgh, pointed to the precedent of Iceland which leased out its airbase to Nato for five decades after it became independent.

He added: “I am opposed to nuclear weapons on grounds of cost, morality and lack of effectiveness, but an independent Scotland will not be so awash with cash that it can ignore an asset such as Faslane, which could attract a rental of £1.1bn a year.”

Ramsay rejected the proposal. “It is perfectly understandable that the UK Government would want to lease the base. But one would assume this would not be acceptable to the Scottish Government to do so. The Scottish National party have a policy of removing nuclear weapons swiftly from Scottish soil,” he said.

“Nuclear weapons could destroy human life and indeed most life on the planet. It has been estimated that even a limited nuclear exchange then billions of people would die in the first instance and billions more around the globe as a result of radiation.

“If they are used people die in their billions and human life could be made extinct. We are looking at an extinction event.”

He also believed that it would be a tactical error for an independent Scottish Government to lease out Faslane as a short term measure as the move could provide an incentive for the UK Government to slow down negotiations in removing the weapons.

Last month the SNP CND group published a roadmap setting out the process of getting rid of Trident.

It anticipated three main steps: “Step one is ending operational deployment of the four Vanguard Class submarines that carry the Trident missiles. One submarine is always on patrol. Step two is removal of the keys and the triggers which would then be secured in a safe place on land.

“Step three is to disable the missiles. If key aspects of the guidance and control system are removed then a targeted launch is impossible. It should be noted that the actual missiles are rented from the US Navy.”

In 2016 the House of Commons backed the renewal of the UK’s Trident nuclear weapons system to beyond the early 2030s by 472 votes to 117, approving the manufacture of four replacement submarines at an estimated cost of £31bn.

Trident is the colloquial term used for the UK nuclear weapons system which comprises three main elements and has a vast supporting infrastructure.

Four Vanguard class submarines (SSBN) which maintain continuous at-sea deterrence (CASD), meaning that one vessel is always on patrol (Operation Relentless). The submarines are based at Faslane and the warheads are stored, processed and maintained at the Royal Naval Armaments Depot at Coulport.

In-service maintenance of the Vanguard class is conducted at Faslane; while deep maintenance/refit is conducted at HM Naval Base Devonport in Plymouth.

The decision to acquire Trident was announced in a Statement to the House of Commons in July 1980. A parliamentary debate, and vote, endorsing the Government’s decision was held in March 1981.

From the decision in 1980 it took 14 years to complete the acquisition of the Trident capability with the first Vanguard class submarine entering service in December 1994.