NICOLA Sturgeon has warned Theresa May that it would be a “democratic outrage” if the Prime Minister attempted to block a second independence referendum.

The rebuke came as Downing Street backed Defence Secretary Sir Michael Fallon's declaration that Nationalists should "forget it" if they believed Westminster would sanction a second independence referendum for Scotland.

A spokeswoman for the Prime Minister said the view of Mr Fallon - which provoked a furious backlash from pro-independence Scots - was “consistent with our position that it was settled in 2014”.

Read more: Successful Brexit deal will strengthen Union, insists David Davis

SNP MP Pete Wishart later told the House of Commons: “Believe me, a Government with only one MP in Scotland telling the Scottish people they won’t have a say in the future couldn’t be a bigger gift to us…”

Responding to the prospect Westminster would block a second vote on the Union, Nicola Sturgeon said the “arrogance of the Tories knows no bounds”.

She later told MSPs at Holyrood question-time: "Strange is it not that a Tory Party that proclaims it would be so confident of winning a referendum on independence now talks about trying to block it.

"Isn't it the case that the Tories are actually running a wee bit feart?"

In an exclusive Herald interview, Sir Michael Fallon yesterday said the SNP Government did not have a mandate to hold a second referendum because it did not have a majority at Holyrood and, when asked if the UK Government would issue a Section 30 Order to enable the Scottish Parliament to hold one, said: “No, forget it. The respect agenda is two-way."

Read more: Successful Brexit deal will strengthen Union, insists David Davis

He added: “[Ms Sturgeon] is constantly asking us to respect the SNP Government but she has to respect the decision of Scotland to stay inside the UK in 2014 and the decision of the UK to leave the EU. Respect works two ways."

The Secretary of State, who was in Midlothian visiting MacTaggart Scott, a firm that makes lifts for warships and submarines, was challenged about his view that the UK Government, as the constitutional authority, would refuse to facilitate another referendum, meaning one could not legally take place before May 2020.

Asked about Westminster blocking a second independence poll, Sir Michael avoided a direct answer, telling BBC Radio’s Good Morning Scotland programme: “There is no need for a second referendum.

“The Scottish Government should be getting on and dealing with the things the Scottish Government was elected to deal with. Nicola Sturgeon is simply trying to divert attention away from her own failure. The focus should be on the things that matter to the Scottish people - schools, hospitals and jobs - and not all this theoretical talk of a referendum.”

In response, the First Minister said: “The arrogance of the Tories knows no bounds. They now think they can do what they want to Scotland and get away with it; not content with trying to drag us out of EU against our will with the support of just one MP out of 59 in Scotland, they are now suggesting they might try to block the nation's right to choose a different path.”

Read more: Successful Brexit deal will strengthen Union, insists David Davis

She went on: “Any Tory bid to block a referendum would be a democratic outrage but would only succeed in boosting support for both a referendum and for independence itself; something which the Prime Minister has previously indicated she understands all too well.”

Ms Sturgeon insisted her government had an “unequivocal” mandate, pointing out how the SNP's 2016 manifesto had made explicitly clear that the Scottish Parliament should have the right to decide on an independence referendum if Scotland faced being taken out of the EU against its will.

“No Tory Westminster government has a right to stand in the way of that,” she declared.

Later in the Scottish Parliament, the First Minister noted: “It was the Tories, after all, who put us in the position of being taken out of the European Union against our will and with the support of only one of the 59 MPs in the country."

At Westminster, Mr Wishart, the SNP’s Shadow Leader of the House, referred to The Herald story and called for a ministerial statement, telling MPs: “Believe me, a Government with only one MP in Scotland telling the Scottish people they won’t have a say in the future couldn’t be a bigger gift to us on these benches.”

But David Lidington, the Commons Leader, replied: “The Prime Minister cannot have been more emphatic in making it plain we are determined to consult the Scottish Government, the Welsh Government and the Northern Ireland Executive about how their interests and the people whom they represent are affected by the process of withdrawal and the negotiations on which we shall shortly embark.”

Next week, UK and Scottish Government ministers are due to meet in London to “intensify” their talks on whether or not Scotland could have a differentiated deal on Brexit.