In a day of drama, May's position seemed suddenly weaker when junior justice minister Phillip Lee, who has always been critical of the government's Brexit strategy, resigned and said he would vote against the government.
In other words, in the event of a divorce deal that the Commons refused to accept, MPs would be able to set a new course for Brexit. The European Union Withdrawal Bill, meant to enact Britain's exit from the bloc, has had a rocky ride through Parliament.
He said: "I'm conscious that if we're to make progress we ought to try and do this by consensus, but he must also understand the difficulty the House is in when it is faced with this kind of choice".
Opening the debate, Brexit Secretary David Davis insisted the government would abide by three principles to defend the will of the British people.
The Government is against the plan, believing it sends the wrong message to Brussels regarding the UK's negotiating goals.
"It's not practical, it's not desirable and it's not appropriate", Davis said.
Dominic Grieve tabled an amendment last night which forced the government's hand over the issue of a meaningful vote.
In a tense afternoon in parliament, Remain MPs said they had received death threats and brandished a copy of the Daily Express newspaper, which ran a headline saying: "Ignore the will of the people at your peril".
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The president then addressed his successes with the rogue nuclear nation to display that the arrangement was a win for the US. The spokesman said Trump told Moon he would send Pompeo to Seoul immediately after the summit to explain its outcome.
Earlier Phillip Lee - who quit as a justice minister to oppose the government on Brexit - received a round of applause after he set out his stance.
A file photograph of justice minister Phillip Lees.
Tory rebels claimed that the government had agreed to specific proposals from leading backbench remainer Grieve to address concerns over what would happen if parliament rejected the final Brexit deal, or talks with the European Union were to break down.
The change reduces the likelihood that Britain could leave the European Union without a deal if it does not like the divorce terms.
Theresa May has narrowly avoided a humiliating defeat over the Brexit bill after Conservative rebels accepted significant concessions from the government on the "meaningful vote" when it returns to the House of Lords next week.
Starmer's call comes as lawmakers are bracing for a fierce parliamentary debate over Britain's European Union divorce bill.
MPs are preparing for a two-day debate on the legislation to leave the EU. It also attacked the unelected nature of the House of Lords (which traditionally scrutinizes laws passed to it by the elected lower chamber), linking it to a perceived attempt to frustrate the Brexit process.