MPs who help Theresa May get a “cobbled-together” Brexit deal through Parliament would be guilty of a “dereliction of duty”, Nicola Sturgeon has warned.

The Scottish First Minister used a speech in London on Monday to urge Westminster politicians to vote down any compromise deal the Prime Minister can strike with Brussels.

She accused the UK Government of “threatening us with fire, to make us choose the frying pan”, and argued that any deal that is presented to the Commons was likely to be deliberately vague about the future relationship and damaging to the UK’s interests.

Ms Sturgeon told an audience at the Royal Society of Arts that voting down the Prime Minister’s proposal would allow a deal keeping the UK in the customs union and single market – which the SNP wants – to be presented instead.

Voting against “a bad or blindfold Brexit” was not a vote for no-deal, she argued, but “the only chance the House of Commons will have to reset these negotiations and think again before it is too late”.

She said: “As the crucial vote looms closer, it is also time for individual members of the House of Commons to consider what compromises they see as justified – and which are not – if they are to serve their constituents, and the wider public interest.

“If they do that, I believe that a commonsense outcome could yet be found.”

Nicola Sturgeon
Ms Sturgeon has said the SNP’s strong preference is to remain in the EU (Jane Barlow/PA)

She added: “For MPs to support a bad or blindfold Brexit – a cobbled-together withdrawal agreement and a vague statement about our future relationship – would, in my view, be a dereliction of duty.”

In the June 2016 referendum, Scotland voted by 62% to 38% in favour of remaining in the EU.

As part of her speech, the First Minister presented a new paper from the Scottish Government – Scotland’s Place in Europe: Our Way Forward.

It noted that the “core” of the proposal was the same as it set out in December 2016.

Writing in her foreword to the paper, Ms Sturgeon said: “The Scottish Government, in line with the overwhelming vote for Remain in Scotland, supports continued EU Membership. Remaining in the EU continues to be our strong preference.

“Nevertheless in December 2016 we set out a compromise plan to keep Scotland and the UK in the European Single Market and Customs Union to limit the damage of Brexit as much as possible.

“It is therefore simply incorrect for the Prime Minister to say that there is no alternative to Chequers.

“In fact, the UK Government’s position is increasingly absurd – insisting on pursuing proposals they have been told will not work while rejecting a plan that will.”

She adds: “With crucial decisions coming up over the next few weeks and months at EU level – and in the House of Commons, where the UK Government must seek the approval of the UK Parliament – it is vital to break the deadlock.

“For the Prime Minister and the UK Government it is time to face reality. For MPs at Westminster it is time to come together in a commonsense coalition to minimise the Brexit damage.”

A spokesman for the Department for Exiting the European Union (Dexeu) said: “We will have an ambitious course outside of the EU that enhances our prosperity and security and that genuinely works for everyone across the UK.

“We have put forward a precise and credible plan for our future relationship with the EU and look forward to continuing to engage with the EU Commission on our proposals.”

Scottish Conservative constitution spokesman Adam Tomkins said there was “nothing new” in the speech, which had been made “in the hope of drumming up the prospects for Scottish independence”.

He added: “If the SNP doesn’t back a deal, it is automatically supporting a no-deal scenario – something the nationalists have admitted would be bad for Scotland.

“And, of course, they don’t care if outcomes are bad for Scotland, so long as they’re good for the prospects of another independence referendum.”