NICOLA Sturgeon has said it is “news to me” that the SNP manifesto will not include a clear commitment to hold a second independence referendum.

Reports have claimed the party policy document for the upcoming Scottish parliamentary elections in May will simply pledge to hold a second poll if there is clear evidence a majority of voters support independence.

But on Twitter, the First Minister, responding to them, said: “News to me! Manifesto not finalised yet.”

In October at the SNP conference, Ms Sturgeon argued that it would be wrong to propose a new vote without strong and consistent evidence that significant numbers of No voters had changed their minds. Party insiders suggested that this meant opinion polls had to show at least 60 per cent support for a year to ensure a strong chance of winning the vote.

Earlier, Jim Sillars, the former deputy leader of the SNP, expressed alarm at the claim that a clear commitment to a second independence referendum would not be included in the Nationalists’ manifesto.

He argued that such a move would mean the UK Government would be under no obligation to grant Holyrood the legal power to stage a second poll.

“I don’t think the Cameron government would budge an inch,” declared Mr Sillars. “The claim would be: you didn’t ask for a mandate, therefore you don’t have a mandate, therefore there’s no need for us to respond to your request for one. We’d come up against a brick wall," he added.

Last July in an interview with The Herald, David Mundell, the Scottish Secretary, urged Ms Sturgeon to “come clean” and “be honest with the people of Scotland” by saying if she would include a clear commitment to a second referendum in the SNP’s Holyrood manifesto.

Crucially perhaps, the Secretary of State stressed that if the Nationalists' policy programme was vague about a second poll then it could not be advanced later as a mandate; suggesting Westminster - which remains the constitutional authority for holding legal referendums - would not sanction another independence poll.

He said: "Using a wording that allows maximum flexibility would hardly be capable of being held out as a mandate for a second referendum.

"If you want a second referendum, be upfront and be honest with the people of Scotland that that is your priority ahead of how much tax they pay, what welfare benefits they get, what happens in our schools or hospitals. It's time to be honest about it.”

Following the General Election David Cameron was adamant that the issue of Scottish independence had been "settled". The Prime Minister said: "There isn't going to be another referendum."