Theresa May is “running scared” of Scotland having another say on its future, Nicola Sturgeon has claimed, after the Prime Minister firmly ruled out facilitating a second independence referendum.

The rhetorical clash came as MPs prepared for another confrontation between Parliament and Government over Brexit by setting down more amendments for Tuesday’s Commons vote, seeking to extend the Article 50 process and attempting to block a no-deal outcome.

READ MORE: Herald poll: Scotland should have independence referendum after Brexit 

Last night, there were more signs that Jeremy Corbyn might be preparing to back a move spearheaded by Labour colleague Yvette Cooper, to put back Brexit Day in an attempt to stop Britain crashing out of the EU. The Labour leader held “positive” talks in his parliamentary office with the Yorkshire MP.

However, earlier in Brussels, Michel Barnier, the EU’s chief Brexit negotiator, warned the backbench bid was doomed to failure unless a majority for an alternative agreement at Westminster was found.

And he appeared to dash the Prime Minister’s hopes of changing the terms of the Irish backstop by claiming slapping a time limit on it would render it "useless".

Meanwhile, in an unexpected twist, ardent Brexiteer Jacob Rees-Mogg raised the prospect of the Queen being called upon to suspend Parliament, so that any attempt to stop a no-deal Brexit could be halted.

After another hourlong meeting in Downing St, the First Minister emerged exasperated at what she regarded at its total lack of progress.

Ms Sturgeon said the Prime Minister had shown “no real sign of any willingness to compromise” on her Brexit red lines and that her priority was “playing to the right wing, hard line Brexiteers” of the European Research Group and the Democratic Unionists; an approach, she claimed, was “destined to fail”.

The FM declared: "It is taking the entire country and Scotland in particular…down the wrong road; one that is going to be devastating for our economy.”

Earlier during another fractious PMQs, the issue of Scotland’s constitutional future was raised by Stephen Kerr, the Conservative MP for Scotland, who hailed the UK as the “most successful political union that the world has ever known”.

To Tory cheers, the backbencher urged Mrs May that when Ms Sturgeon demanded another independence poll, she should “side with the majority of the people of Scotland and firmly tell her: no”.

READ MORE: Iain Macwhirter: Two different paths on the march towards indyref2 

In response, the PM claimed that, sadly, the SNP was “out of touch with the people of Scotland” and had not yet heard the message delivered in 2014, adding: “The last thing we want is a second independence referendum. The United Kingdom should be pulling together and should not be being driven apart.”

But the FM claimed: "The PM fears she would lose another Scottish independence referendum so she is running scared of the verdict of the people…[Those] who are confident in their arguments don't run away from the verdict of the people.”

She went on: "People in Scotland are probably getting sick and tired of what the PM wants. What the PM wants is not the most important thing here; what Scotland needs is what matters most.”

READ MORE: Theresa May - 'The last thing we need is a second Scottish independence referendum' 

Asked how so-called indyref2 could be realised given Mrs May held the constitutional power and was adamant she would not facilitate one, Ms Sturgeon replied: “You can’t stand in the way of people having the right to choose indefinitely. The PM’s position has never been a sustainable one.”

She added: “Brexit is demonstrating on a daily basis right now that Scotland needs the ability to take her own decisions so we are not dragged down the wrong path by Tory ideologues and we don't constantly face the prospect of having policies imposed by Westminster governments that we did not vote for.”

For its part, No 10 did not say how the PM/FM meeting had gone but announced how the FM and her Welsh counterpart, Mark Drakeford, had been invited by Mrs May to attend “all relevant meetings” of a new Cabinet sub-committee on Brexit preparations, covering both a deal and no-deal outcomes.

“This builds on the increasing engagement in recent months between the UK Government and the devolved administrations and our commitment to give them an enhanced role in the next phase of the Brexit process, respecting their vital interests in these negotiations,” said a Downing St spokesman.

Elsewhere, Stephen Barclay, the Brexit Secretary, told the Lords EU Committee, if MPs did not back an EU withdrawal agreement, they would have to choose between a no-deal exit or revoking the decision to quit the bloc.

He insisted the Government was "absolutely not" trying to run down the clock to the scheduled March 29 Brexit Day to put pressure on the Commons to back a revamped version of Mrs May's exit plan.

In other developments:

*Trade Secretary Liam Fox warned that overturning the referendum result would be politically "calamitous" and worse than a no-deal outcome

READ MORE:  Liam Fox: Overturning EU referendum would be "calamitous"

*George Osborne, the former Chancellor, said a no-deal exit would be akin to playing Russian roulette, “a game which you should never play, because there’s one-in-six chance bullet goes into your head,” and that extending the Article 50 process was “now the most likely option”;

*John McDonnell, the Shadow Chancellor, confirmed it was “highly likely” Labour would back the Cooper amendment in next week’s Commons vote to block a no-deal Brexit by extending Article 50 to the year-end, if there were no agreement by February 26;

*the Liberal Democrats tabled an amendment, proposing the establishment of a cross-party Business of the House Committee, which would decide when parliamentary time should be made available for Brexit debates and legislation, including on a second referendum with Remain on the ballot paper and

*given the number of Brexit bills that still need to be processed through Westminster, there is a growing expectation that the scheduled February recess, from the 14th to the 25th, will be cancelled.