“We would like within a few weeks for our UK friends to set out their expectations for us”
The Prime Minister raced to Brussels to beg the 27 member states to give an assurance that would be able to amend her criticised agreement.
But, despite her desperate calls, the EU leaders told her firmly there would be no chance for more talks.
Jean-Claude Juncker, the European Commission president, said: “We dont want the UK to think there can be any form of renegotiation, that's crystal clear.
“We can add clarifications but no real changes. There will be no legally binding obligations imposed on the withdrawal treaty.”
He also slammed the UK over its lack of clarity.
Mr Juncker added: “We also think that in terms of the future relationship with our UK friends need to say what they want, instead of asking us to say what we want.
“We would like within a few weeks for our UK friends to set out their expectations for us because this debate is sometimes nebulous and imprecise and I would like clarifications.
“As we dont know what the collective reactions will be from the Europe 27 and the UK, the Commission on the 19th December will publish all the information that is generally useful for the preparation of no deal, this is preparedness.”
The humiliating slap down comes as Mrs May hobbled through a leadership challenge on Wednesday.
Amid widespread disquiet over her leadership and handling of Brexit, the Prime Minister has put down a Eurosceptic rebellion within her party by winning the vote by a margin of 200 to 117.
Chairman of the 1922 Committee Graham Brady announced the result to applause and cheers in the House of Commons.
May was all smiles when she arrived at Downing Street after she did enough to convince Tory MPs to back her.