MPs voted to defeat amendments to the EU Withdrawal Bill which were debated in the House of Commons, including amendments which sought to keep Britain in the single market and a customs union with the EU.
The Lords amendment would force the government to prioritise an EEA deal - the so-called Norway Model - in negotiations with the EU.
There is no time to get the wording of the compromise text wrong because it will probably be debated and voted on in the House of Lords on Monday, according to one senior government official. Several pro-EU Conservative lawmakers said they would join the opposition in voting against the government.
This is despite his constituency voting almost 80% to remain in the June 2017 referendum.
And as May and her government have repeatedly ruled out doing anything which would threaten the integrity of the United Kingdom, then it is hard to see how this won't point towards Britain accepting anything but the softest of soft Brexits.
But she told MPs that "the government's hand in negotiations can not be tied by parliament".
Theresa May met pro-EU Tories in her private room in the Commons moments before a crucial vote to hear their demands for a truly meaningful vote on the final exit deal.
He said Mrs May had promised to table a fresh amendment based on his own proposal for Parliament to be consulted on the way forward if no deal is agreed by the end of November.
So - if and when the UK government finally reaches agreement on what it desires as the future EU-UK relationship - the warning from Brussels is this: pay attention to the Irish border; whatever else is agreed it could still bring the whole Brexit deal crashing down.
MPs started debating the amendments to the bill just after 1pm on June 12.
Conservative Brexit campaigners accused those in the party who indicated they would vote against the government of not respecting the referendum result. Should lawmakers prevail, the direction of Brexit could change. "Putting a decision off doesn't make it any easier".
The former Justice Minister made the unexpected move while he was giving a speech at the Bright Blue think tank and was applauded by Labour Remainer MPs in the chamber and praised by leading Tory rebels including Anna Soubry and health select committee chairwoman Sarah Wollaston.
The concession came after intensive horse-trading on the floor of the House of Commons, with chief whip Julian Smith shuttling between Tory backbenchers during debate on Lords amendments to the EU Withdrawal Bill.
But Brexit campaigners feared it could weaken Britain's negotiating stance in talks to leave the European Union and the Brexit ministry was quick to put out a statement saying: "We have not, and will not, agree to the House of Commons binding the government's hands in the negotiation".
If May is defeated in the House of Commons it will be yet another blow to a prime minister whose authority has been challenged several times since last year's election. She had nearly lost a general election she never needed to call, squandering her Conservative Party's overall majority and forcing her to rely on the support of the smaller Democratic Unionist Party.
An agreement that defused a potential rebellion over handing parliament more control over Britain's exit from the European Union looked in danger of unraveling on Wednesday, when the two camps argued over the shape of a possible compromise on a "meaningful vote".