A group is to be set up to examine ways of preventing a replacement for the Trident nuclear weapons system being based on the Clyde.

The group, which will be backed by the Scottish Government, will look at how the Scottish Parliament can use its powers in areas such as planning, transport and the environment to block the UK Government's £20bn renewal plan.

Scottish Government ministers were among those at a summit in Glasgow yesterday examining the impact of removing Britain's nuclear deterrent from Scotland.

Church leaders, trade unionists and anti-nuclear campaigners were also there to express their opposition to the plans, announced by Tony Blair earlier this year when he was still Prime Minister.

Neil Smith, a spokesman for the Ministry of Defence, also attended the meeting and claimed that scrapping Trident would lead to the closure of the Royal Navy's Faslane base and cost about 7000 jobs.

Bruce Crawford, the Scottish Government minister for parliamentary business, insisted removing Trident was the clear wish of the majority of Scots and it was up to Holyrood to find ways of making it happen.

He said: "We have a duty to represent the views of the Scottish people.

"We cannot, of course, use our devolved responsibilities to hinder or block decisions by the UK Government on reserved matters. We can, however, consider the impact on Scotland and on our devolved responsibilities of the UK Government's plans to replace Trident and to continue to base nuclear weapons in Scotland.

"We are fully entitled to form an opinion on these matters and to do what we can to persuade the UK government to change its position.

"Those who say otherwise are blind to the changes since devolution and are out of step with the changed political reality in Scotland."

The UK government is planning four new nuclear submarines, at a cost officially estimated at £15bn to £20bn.

Defence matters are reserved to Westminster, but Mr Crawford said the working group would be asked to examine what the economic future would be for Faslane and the area if Trident was scrapped.

It will also lobby the UK government about what Mr Crawford described as "weaknesses" in its nuclear licensing framework, and examine the legality of Trident under international law.

The minister said the group would also look at the possibility of the Scottish government being represented at a Non-Proliferation Treaty conference in 2010.

Mr Smith, who is the Royal Navy's communications chief at Faslane, warned that the economic consequences for the wider West Dunbartonshire area would be grim if Trident was not renewed.

He said that, as well as the 7000 people directly employed at the base, about 3000 people were indirectly employed as a result of Trident's presence, generating £267m for the economy.

"If there is no strategic nuclear deterrent there is no need to have the Clyde Naval base," he said.

Every political party was invited, but Green MSP Patrick Harvie was the only non-SNP representative to attend.

George Foulkes, the Labour backbencher, described the summit as "a ridiculous waste of time and taxpayers' money". "This is a reserved issue over which they have no control," he said.

Mr Harvie said: "On such a moral, legal and internationally important issue (Labour's) oppositionalism for the sake of it is deeply disappointing."