Labour's Sir Keir Starmer said that after the 149-vote defeat of her Withdrawal Agreement on Tuesday, Mrs May's mantra of "my deal or no deal" should be "dead and buried".
"Once again, she's putting her party's interests ahead of the public interest", said a Labour Party spokesperson.
He said: "Isn't it time she moved on from her red lines and faced the reality of the situation that she has got herself, her government and this country into".
But ministers said products from the European Union including beef, pork, chicken, butter, cheese and fish would also be subject to import taxes expected to push up prices in the supermarkets from March 29 if there is no deal.
Conservative MPs, only 75 of whom voted against the plan this time after 118 of them voted against it in January, will be able to vote freely going forward, May promised.
She said: "Obviously we continue to be working to leave in an orderly fashion with a deal, but we have made funding available".
But although she managed to convince about 40 Tory MPs to change their mind, it was not almost enough to overturn the historic 230 vote defeat she suffered on the same deal in January.
Heidi Allen MP
"If the deal is defeated tonight it is impossible to imagine that the prime minister would allow this to drift into next week, when Oliver Letwin will table a bill for the House of Commons to take over the negotiating process".
What isn't clear is how the prime minister actually intends to dig herself out of this terrible political hole.
THE public must have a say over Brexit in a second European Union referendum, MP Drew Hendry insists.
Tonight they will vote on leaving with no deal.
"He used to believe that too, why is he just trying to frustrate it?"
All three Brighton and Hove MPs, Labour's Peter Kyle and Lloyd Russell-Moyle as well as the Green Party's Caroline Lucas, voted against the deal.
Leading Tory Remainers and Brexiteers, including Dominic Grieve and Boris Johnson, have suggested the prime minister's deal is now "finished" and other options must be brought forward.
Mr Boles added the PM must go as soon as a deal is agreed.
The EU's chief negotiator Michel Barnier again insisted there will be no further offer from Brussels apart from the deal already on the table.More news: NY AG Office Files Subpoenas Seeking Trump Organization's Records
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