SNP MPs were left fuming after Theresa May snubbed Ian Blackford in today’s Brexit debate.

While the Prime Minister sat patiently, listening to the opening speeches, as soon as the SNP’s Westminster leader got to his feet, May stood up and walked out.

"I must say that it's disappointing that as I stand up to speak on behalf of the Scottish Nationalist Party and the Scottish Government, that the Prime Minister has walked out the chamber,” Blackford told MPs.

He added: "I regret that that is the response we get from the Prime Minister. All too Common, I must say.

"And this on the day the Prime Minister told us the UK would leave the EU with a deal. She's come to parliament defeated and desperate.”

Amid rumours that the government facing a narrow defeat were opening their cheque books in a bid to win over wavering Labour MPs, the SNP leader appealed directly to Jeremy Corbyn’s party.

"We will not allow ourselves to be dragged out of the European Union. And it will usher in the day that the thing so many members of this House tell us they want to preserve, the union of the United Kingdom, that will be over.

"Because Scotland will and Scotland must become an independent member of the European Union," Blackford said.

Labour’s Ian Murray said Blackford was not being entirely truthful. He tweeted: “You are making this up as you go along. Are you pumping out this rubbish to cover up your embarrassment of abstaining on the customs union which meant it failed? Attacking Labour by making things up is very 1979 of you. Is it because you are having your own party rows on this?”

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Despite the government’s desperate largesse, it looks as if most Labour MPs will give May’s deal a bodyswerve.

The vote is expected at 2.30pm, with the result around 2.45pm.