UK may never leave EU if deal rejected: May
So far there is little sign of May getting the concessions from Brussels that she says would reverse her previous defeat.
"It needs just one more push to address the final, specific concerns of our parliament," May said in a speech in Grimsby, a port town in northern England where 70 percent of voters backed the decision to leave the EU in the 2016 referendum.
"So let's not hold back. Let's do what is necessary for MPs to back the deal on Tuesday," she said, warning that "no-one knows what will happen" if it is rejected.
London and Brussels are at loggerheads over the so-called Northern Irish backstop, which seeks to prevent the return of physical border controls between Northern Ireland and Ireland - the only land frontier between the United Kingdom and the bloc.
May wants legally binding assurances from the EU that Britain will not be trapped permanently in the backstop, which involves keeping Britain in a customs union with the bloc.