Hard-line Conservative lawmakers triggered a no-confidence vote in British Prime Minister Theresa May on Wednesday, increasing uncertainty over whether she can save a controversial draft Brexit deal.

The parliamentarian responsible for internal leadership challenges, Graham Brady, said the vote would take place between 18:00 and 20:00 UTC on Wednesday evening.

He announced the decision after receiving 48 letters from rebel lawmakers requested a vote, the minimum number required to trigger a leadership challenge.

May said she would contest the vote in her leadership of the Conservative Party "with everything I've got."

Read more: UK leadership challenge: How does it work?

All 317 Conservative lawmakers can cast a vote in the secret ballot, with May needing a simple majority, or 159 votes, to win.

Based on statements of support by Conservative parliamentarians, it appears that May should keep her post.

Brexit deal discontent

The leadership challenge comes as May tries to assuage widespread discontent in Parliament over the draft deal she had negotiated on the United Kingdom's planned exit from the European Union on March 29.

On Monday, May postponed a parliamentary vote on the deal in response to expectations that a significant majority of lawmakers would reject it. A new vote is set to take place before January 21.

Former British minister Owen Paterson, one of those to submit a letter of no confidence to trigger the vote, described the deal in his letter as "so bad that it cannot be considered anything other than a betrayal of clear manifesto promises."

Conservative supporters

At least 100 other Conservative politicians, including Home Secretary Sajid Javid and Work and Pensions Secretary Ambur Rudd, said publicly that they were behind May, according to a count by Reuters news agency.

Foreign Secretary Jeremy Hunt said that a leadership contest was "the last thing the country needs" and that May was "the best person to make sure we actually leave the EU on March 29."

Former Prime Minsiter David Cameron, who called the 2016 Brexit referendum, also backed May. "We need no distractions from seeking the best outcome with our neighbours, friends and partners in the EU," he wrote on Twitter.

'Ready to fight'

Speaking outside 10 Downing Street, May said that any leadership change could give control of Brexit negotiations to the opposition Labour Party under Jeremy Corbyn, potentially delaying or halting the Brexit process.

"Through good times and bad over the last two years my passionate belief that this deal is obtainable … has not wavered. And it is now within our grasp," she said. 

"I stand ready to finish the job," she added in a speech that repeatedly alluded to her first as prime minister in 2016.

Later, at an unusually heated parliamentary session of Prime Minister's Questions, Corbyn slammed her decision to postpone the parliamentary vote on the deal, calling May's behavior "appalling."

May, in her turn, accused Corbyn of not wanting Brexit at all and said that the vote would be held in due time amid ongoing discussions with EU leaders.

Challenge procedures

If May wins, party rules say there cannot be another challenge for a year. If she loses, she will have to resign and is barred from running in the ensuing leadership contest. Her successor as Conservative leader would automatically become prime minister without the need for a national election, albeit potentially inheriting a minority government.

Opposition Labour Party leader Jeremy Corbyn has resisted pressure from within his party, and especially from other opposition parties like the Greens and the Scottish National Party (SNP), to call a confidence vote against May's government in Parliament where all MPs could vote.

In view of the turmoil in London, German Chancellor Angela Merkel noted that things were "in flux" there. She said that "we [the EU] do not have any intention of changing the withdrawal agreement," but that Germany remained committed to securing an orderly British withdrawal.

Merkel met with May on Tuesday as part of the British premier's visits to various EU leaders in search of reassurances on her deal. 

 tj, am, amp/msh (Reuters, dpa)

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