THE UK Government last night gave the green light to a referendum on Scottish independence, conceding Alex Salmond has "the majority and the authority" to ask whether to break up Britain.

Michael Moore, the Liberal Democrat Scottish Secretary, said the Westminster Coalition would not put up any obstacles to a referendum, or try to stage a rival referendum on its own terms in the hope of securing a No vote.

He also said he believed a Salmond-led referendum would be legally competent in spite of some Unionist politicians questioning its validity, adding that the UK Government would not put up legal or constitutional hurdles to it.

The hands-off approach clears the way for Salmond to hold a referendum with a question of his choosing, when he chooses, using his overall majority to pass the legislation at Holyrood.

The First Minister has said the vote would be in the second half of the five-year Parliament, but delay could allow a No campaign to build up a head of steam and ruin his chance of success.

Years of public sector cuts could also deflate the feel-good factor around the SNP in the wake of its historic election win on Thursday.

Westminster’s insistence that everything now rests with the First Minister allows a No campaign to mobilise, and means the pressure is now on Salmond to deliver a Yes vote or suffer a backlash from his own party.

Following the election, Lord Forsyth, the former Conservative Scottish Secretary, called for the Scotland Bill currently at Westminster to be amended to include a referendum in order to take control of the question and the timing of a poll away from Salmond.

However, after discussions with Prime Minister David Cameron on Friday, Moore said the ball was entirely in Salmond’s court.

“The First Minister has made clear his intention to proceed with [the referendum],” he said. “He has the majority and the authority to proceed on that basis. It’s for him to determine when he wishes to do it, and what order of priority he gives to it. As a UK government we will not be putting obstacles in the way of any referendum.”

However, Moore added that he personally saw an independence referendum as a two-stage process, with an initial ballot leading to negotiations between Edinburgh and London, then a second vote on whether to ratify the product of those talks.

Asked if he thought a referendum led by Holyrood would be legal given the Scotland Act reserves constitutional issues to Westminster, Moore said: “It entirely depends on how this is structured. We will not stand in the way of this happening.

“How it’s structured will need to comply with the law to avoid challenge, but I think we’ll all understand what it is we’re being asked to vote on.”

He added that as a LibDem and supporter of the union, he would campaign for a No vote.

And he said Cameron and Salmond would hold further talks on the issue, saying: “We’ll work through the detail with the First Minister should he bring forward that proposal.”

Salmond said Moore and Cameron were showing a “very sensible attitude” to the referendum. On Lord Forsyth’s proposal to amend the Scotland Bill, he added: “Lord Forsyth’s days are over

… I think the debate should be among those people who’ve been elected as opposed to others.”

Deputy First Minister Nicola Sturgeon said the economy and jobs would be at the heart of a Yes campaign.

She said: “Independence is not an abstract process. It’s about our ability as a country to grow our economy and be prosperous.”

Salmond has previously said there could be more than one option on the ballot -- the status quo, enhanced tax powers for Holyrood, and whether people wanted the government to negotiate with Westminster on independence for Scotland.

If the winner of a multi-option ballot was decided by proportional representation, as Salmond has suggested, he might only need a third of voters to back independence to claim a win.

Regular polling shows around a quarter to a third of people support separation from the UK.

Annabel Goldie -- whose leadership of the Scottish Conservatives is in question following a poor result on Thursday -- last night tried to position herself at the front of the No campaign.

She said: “For the foreseeable future, Scottish Labour will be more concerned with its own internal issues than those of the country. The LibDems are a spent force at Holyrood. It falls to us to be the voice of opposition and the champions of the union. We will not shirk from these responsibilities.

“The ball is now in Alex Salmond’s court. He has to chose between five years of constitutional uncertainty, or take a brave pill and get on with the referendum.”

Cameron has said that he will “campaign to keep our United Kingdom together with every single fibre that I have”.

The SNP also stepped up demands to change the Scotland Bill to give Holyrood power over corporation tax, immediate borrowing powers of up to £5 billion for capital projects, and devolution of the Crown Estate, which is expected to raise millions of pounds from the renewable energy boom by leasing the seabed to offshore windfarms.

But Moore said although borrowing powers in the bill might be accelerated, the figure would be £2bn, and added that the Crown Estate would be reformed but not devolved.

He also ruled out devolving corporation tax or even consulting on the idea, as is currently happening in respect of Northern Ireland.

Sturgeon said she expected Moore to improve on his “opening gambit”.