Theresa May has vowed to battle on ‘with everything I have got’ as she faces a leadership challenge sparked by her chaotic Brexit.
The prime minister’s leadership hangs in the balance after 48 letters asking for her to step down were sent to 1922 Committee chairman Sir Graham Brady.
Conservative MPs will vote this evening with May needing a simple majority to see off the challenge.
If she wins she cannot be challenged for another 12 months but if she loses a contest will begin with the final two candidates voted for by the membership.
Speaking outside Downing Street May said: ‘Sir Graham Brady has confirmed that he has received 48 letters from Conservative MPs so there will now be a vote of confidence in my leadership of the Conservative Party.
‘I will contest that vote with everything I’ve got.’
She added: ‘I stood to be leader because I believe in the Conservative vision for a better future; a thriving economy with nowhere and nobody left behind; a stronger society where everyone can make the most of their talents – always serving the national interest.
‘And at this crucial moment in our history, that means securing a Brexit deal that delivers on the result of the EU referendum, taking back control of our borders, laws and money, but protecting jobs, our security and our precious union as we do so.
‘Through good times and bad over the last two years, my passionate belief that such a deal is attainable, that a bright future lies ahead for our country, has not wavered and it is now within our grasp.
‘I spent yesterday meeting Chancellor Merkel, prime minister Rutte, president Tusk and president Juncker to address the concerns that MPs have with the backstop, and we are making progress.’
Attacking those that are seeking to topple her she added: ‘Weeks spent tearing ourselves apart will only create more division, just as we should be standing together to serve our country. None of that would be in the national interest.
‘The only people whose interests would be served are Jeremy Corbyn and John McDonnell.’
And in a defiant closing message she said: ‘I have devoted myself unsparingly to these tasks ever since I became prime minister and I stand ready to finish the job.’
Confirming the threshold to spark the ballot had been reached Sir Graham said the vote would be held between 6pm and 8pm in the House of Commons and the result announced this evening.
‘The votes will be counted immediately afterwards and an announcement will be made as soon as possible in the evening,’ he added.
A string of cabinet ministers, including some touted as possible replacements for May, have swiftly come out with statements of loyalty to her.
Home secretary Sajid Javid said: ‘The last thing our country needs right now is a Conservative Party leadership election. Will be seen as self-indulgent and wrong. PM has my full support and is best person to ensure we leave EU on 29 March.’
Foreign secretary Jeremy Hunt said: ‘I am backing Theresa May tonight. Being PM (is the) most difficult job imaginable right now and the last thing the country needs is a damaging and long leadership contest.
‘Brexit was never going to be easy but she is the best person to make sure we actually leave the EU on March 29.’
Environment secretary Michael Gove, another cabinet minister seen as a possible leadership contender, tweeted: ‘I am backing the prime minister 100% – and I urge every Conservative MP to do the same. She is battling hard for our country and no-one is better placed to ensure we deliver on the British people’s decision to leave the EU.’
Brexit-backing international development secretary Penny Mordaunt posted: ‘The prime minister has my full support, not least because she has always done what she firmly believes is in the national interest. Our country needs us all to fight for a good deal and prepare for a no-deal scenario. All eyes and hands should be on that task.’
Others voicing support for the PM included chancellor Philip Hammond, health secretary Matt Hancock, justice secretary David Gauke, pensions secretary Amber Rudd and communities secretary James Brokenshire.
But in a joint statement, the chairman of the European Research Group of Eurosceptic Tory backbenchers Jacob Rees-Mogg and his deputy Steve Baker said: ‘Theresa May’s plan would bring down the government if carried forward. But our party will rightly not tolerate it.
‘Conservatives must now answer whether they wish to draw ever closer to an election under May’s leadership. In the national interest, she must go.’