With EU leaders warning there would be no more changes or negotiations, and less than three weeks to go until the U.K.is due to leave, British lawmakers were facing a stark choice in a vote later: support a deal many consider inadequate or run the risk that Brexit might happen chaotically, or not at all.
Sinn Féin President Mary Lou McDonald meanwhile said: "The British Parliament voted by a landslide to reject the Withdrawal Agreement and Theresa May's latest proposals".
Moscovici said "the train has passed two times" and the European Union will not renegotiate the deal before the scheduled Brexit date of March 29.
It comes amid reports Mrs May will fly to Strasbourg, France in the coming hours in a last-minute bid to save her foundering Brexit divorce deal before it is voted on again on Tuesday local time (Wednesday morning AEST).
This is what Brexit hardliners are hoping for - that they will get another chance to force May to take the United Kingdom out of the bloc with no deal.
Sterling, which has see-sawed on Brexit news, jumped 0.8 percent to $1.3250 in Asian trade and rallied to the strongest against the euro since mid-2017. However, the text of the 585-page withdrawal agreement remained unchanged.
German EU affairs minister Michael Roth, called it "a far-reaching compromise". "There is no alternative".
He added: "I think a meaningful vote with an addendum saying this House will support a deal if such and such is done might be a way of uniting the party or limiting the scale of the defeat". Labour Brexit spokesman Keir Starmer expressed skepticism about whether May had won substantive concessions.
MPs have also been promised that they will be shown any updated legal advice from Attorney General Geoffrey Cox before the debate begins.
At a late-night news conference Monday in Strasbourg, France, May and European Commission President Jean-Claude Juncker announced changes created to overcome lawmakers' concerns about provisions created to ensure the border between EU member Ireland and Britain's Northern Ireland remains open after Brexit.
Parliament rejected May's deal by 230 votes on January 15, prompting her to return to Brussels in search of changes to address the so-called Irish backstop - an insurance policy created to prevent the return of a hard border between Ireland and Northern Ireland.
Juncker said he recommended the deal to the EU Council, which represents member states, and that Irish Prime Minister Leo Varadkar was prepared to back the changes on the backstop. The two sides also agreed to continue working on technology that would do away with the need for border checks. It has the same legal status as the Withdrawal Agreement.
"But let me be clear", May said after the vote tally was read to Members of Parliament in the Commons Chamber. "There will be no further interpretations of the interpretations; no further assurances of the re-assurances - if the meaningful vote tomorrow fails".
The Telegraph said there was "a backdrop of exasperation" to the Prime Minister's trip to Brussels and that a deal will only succeed if there is "no doubt" that the backstop is temporary.
The British parliament voted to reject May's deal in January by 230 votes, the biggest margin of defeat in modern British history.
European Commission spokesman Margaritis Schinas says the EU was "open and willing" to hold talks with the United Kingdom although no further meetings at a political level have been made. It is what we do with the second chance that counts.
The plans for a No Deal Brexit will now be announced this morning after the Tory cabinet's attempt to get the Brexit deal through Parliament was again heavily defeated last night.
May's deal again on March 12, lawmakers will vote over the following two days on whether to leave the European Union without an agreement - an idea likely to be rejected, or to ask the European Union to delay Brexit beyond the scheduled March 29 departure date.
Some British lawmakers underscored that warning, telling their Brexit-backing colleagues that rejecting the deal could lead to Britain's departure being postponed indefinitely.