The EU again stressed on Tuesday that it will not renegotiate the withdrawal agreement that will see Britain exit the EU on March 29.
Conservative MPs will vote from 18:00 GMT to 20:00 GMT.
Some of these Europhile-leaning Brits have argued that the 2016 vote was unfairly influenced by dark money or Russian misinformation.
Home Secretary Sajid Javid added: "The last thing our country needs right now is a Conservative Party leadership election".
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But facing a huge rebellion of her own Tory MPs, primarily over the backstop clause created to keep open Britain's border with Ireland, May conceded she expected to lose and delayed it. She vows to fight the leadership challenge.
If Mrs May does not win the vote there would then be a Conservative leadership contest in which she could not stand. With the U.K.'s leader unable to get out of a German sedan, the moment was called both awkward and symbolic of her struggles in office. "None of that would be in the national interest".
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Toure joined Barcelona in 2007 and won two La Liga titles and the Champions League in 2009. However, he has now left the club after just three months.
Brexiteers in her party have accused Mrs May of selling out Brexit in negotiations, though if they do manage to topple her, Brexit might be delayed, or even cancelled. If she does not, this would kick off a Conservative Party leadership contest, which could take months.
Downing Street has long insisted that the deal agreed by Mrs May in Brussels was the best available, but on Monday, her allies suggested that "nothing is off the table" and that reopening the withdrawal deal was possible. "The victor of that contest would not immediately become prime minister and there could be heavy pressure to call a general election".
The prime minister that promised she would be strong and stable is instead at the top of a party that looks weak and chaotic at a vital time.
However, her motives are derived from her desire to stop Brexit. The only concessions the European Union might consider are some kind of legal opinion or firm commitment that would limit the backstop, but Tory MPs have said that unless the changes were legally binding they won't support the deal, putting Ms.
What does it mean for Brexit?
She was then to see EU President Donald Tusk and European Commission chief Jean-Claude Juncker in Brussels.
On her whistle-stop tour, she also met Dutch Prime Minister Mark Rutte and is headed to Dublin on Wednesday for talks with Irish Prime Minister Leo Varadkar before an European Union summit on Thursday. Among Brexit opponents there is mounting enthusiasm for a chance to have another say.
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He even expelled senior leader Mani Shankar Aiyar from the party for his use of intemperate language against the Prime Minister. The Wikipedia page said Pilot assumed office on December 13, 2018, and succeeded incumbent Chief Minister Vasundhara Raje.
But even is she obtains the reassurances from the remaining member states, it is unclear whether they will convince enough lawmakers to back the deal at a vote set to be held before January 21. "We don't want to stay in the EU", Gove, who serves as environment minister, told BBC radio. MPs can get rid of May without having a replacement lined up.
May said on Monday she was delaying the planned vote as her deal would likely be rejected "by a significant margin".
Graham Brady said the threshold of 48 letters from lawmakers needed to trigger a leadership vote has been reached. She's got a real sense of duty.
May plans to travel to Dublin on Wednesday to continue her whirlwind tour to rescue her Brexit deal.
The backstop is the insurance policy arrangement aimed at avoiding the return of a hard border - physical checkpoints or infrastructure - along the 310-mile (500-km) border between Northern Ireland and the Republic of Ireland after Brexit.
Sterling rose by more than 0.4% against the dollar and by more than 0.2% against the euro on Wednesday morning, after Tory rebels triggered the vote on May's leadership of their party.
"The Conservative Party's internal divisions are putting people's jobs and living standards at risk".
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As tempers frayed, Schumer pressed on, saying there was a proposal on the table that Republicans and Democrats would support. Tuesday's late-morning meeting will be the first gathering of Trump, Schumer and Pelosi ahead of the shutdown deadline.
She is expected to speak with individual Tory MPs during the day before addressing the 1922 Committee at 5pm, immediately before the crucial vote.