Conservative remainers are set to join with Labour and the SNP remainers to force the prime minister into concessions over Brexit. An overwhelming number of MPs voted last week to trigger Article 50 but 114 defied the government.
The SNP accounted for 50, followed by Labour with 47 and seven Lib Dems. Ken Clarke was the only Tory who sided against the government in the vote. Indeed, the veteran pro-EU MP told The Times: "If [May] succeeds... she will start getting into the list of great prime ministers, and if she fails she will be blamed and be in the Tony Blair, David Cameron class of people who were a disaster."
The bill now heads for committee stage and there are fears within Tory ranks that rebels could attempt to scupper Brexit. Anna Soubry, a pro-Remain Conservative MP, said she did not want Theresa May to come back from negotiations without a satisfactory deal.
She told the Andrew Marr show: "The PM has been absolutely clear. If she gets a deal she will be back to the House of Commons – in fact both chambers – and there will be votes, and rightly so.
"But if there is no deal then the Government will determine what happens next. I think it should it come into Parliament. I don't know why people are so fearful of that."
On the other side of the House of Commons, Labour faces its own problems. Jeremy Corbyn ordered a three-line whip to vote to trigger Article 50 but was denied by dozens of his MPs including shadow environment secretary Rachael Maskell, shadow Welsh secretary Jo Stevens, and shadow equality minister Dawn Butler who all resigned their posts to defy the leader.
Speaking on BBC Radio 4 on Sunday, Corbyn suggested he could keep them in his inner circle. "You are asking me a very hypothetical question here. I will be making an announcement during the week." He added: "I am a very lenient person."