Prime Minister's Questions descended into chaos this afternoon, after the entire group of SNP MPs walked out in support of Westminster leader Ian Blackford over challenges to yesterday's Brexit bill.
Blackford had sought an immediate vote to have the Commons heard in private, complaining that little more than half an hour had been given over to debating the devolution amendments to the EU Withdrawal Bill last night.
While Speaker John Bercow initially appeared to say the division could happen immediately, he then said it would have to wait until the end of PMQs, prompting outrage from SNP MPs including Blackford, who refused to return to his seat.
As a result, Bercow banned him from the Chamber for the rest of the day.
As Blackford left, he was joined by his colleagues, some of whom jeered and gesticulated at the Conservative MPs opposite.
In the central lobby immediately afterwards, Blackford told the BBC he would not back down.
"Scotland's voice has not been heard... that's a democratic outrage," he said. "I asked the Prime Minister to bring in emergency legislation so we can have a proper debate... and the Speaker refused to allow a division, which I rightly called for.
"I have a duty... to stand up against betrayal against Scottish people and the power grab that has taken place," Blackford added. "Where is the respect to the Scottish people?"
"This is a constitutional crisis - we will take them on. I am not prepared to sit back and see powers taken from Scottish parliament," he concluded, to a round of applause from SNP MPs behind him.