ONE LAST CHANCE

11pm tonight was meant to be the moment Britain became a proud sovereign nation once more. Instead, Parliament’s in paralysis. To every MP, the Mail says this: Put your country first. Uphold democracy. Back the Brexit deal today. You’ve got...

THERESA May will challenge MPs to finally back Brexit this afternoon – on the day Britain was supposed to leave the EU. In a high- stakes gamble, Mrs May will throw down the gauntlet to Labour and her own Eurosceptic MPs, amid fears that she risks a third, and possibly final, defeat. If she does lose – and Parliament tries to make her accept a customs union and second referendum – allies fear she could be forced to call a General Election as early as next week.

The Prime Minister made her move after deciding to take the dramatic step of splitting her deal in the hope of getting it through the Commons.

MPs will vote only on the ‘divorce’ element of the deal today – and not the political declaration on Britain’s future relationship with the EU.

If Mrs May wins, the date of Brexit would be fixed at May 22, and Britain would not have to hold European Parliament elections the following day. However, if she loses the vote, Mrs May is likely to have to return to the EU to seek another, longer delay – guaranteeing we would elect more MEPs.

A Whitehall source said another defeat for the Prime Minister’s deal could see Brexit delayed for up to five years. ‘once you have taken part in the European elections, there is no limit on the number of extensions you could have during the lifetime of the parliament,’ they said. The warning came as:

A cross-party group of MPs led by Sir oliver

Letwin and Yvette Cooper threatened to change the law next week to force Mrs May to pursue a soft Brexit option, such as a customs union;

■ Boris Johnson, who dropped his opposition to the deal after Mrs May agreed to step down, was reported to have declared it ‘dead’;

■ Former Brexit Secretary Dominic Raab made a bid for the Eurosceptic vote in the coming leadership election by refusing to back the deal and urging Mrs May to go back to Brussels and negotiate;

■ Former chief whip Mark Harper and Tory grandee Crispin Blunt indicated they would now back the deal;

■ Mrs May’s former deputy Damian Green suggested she would ‘soldier on’ as Prime Minister if her deal is defeated, despite ministers warning privately she could not lead the party into another election;

■ Writing in the Mail, Iain Duncan Smith urged his fellow European Research Group members to back the deal, saying ‘ Brussels will have Britain over a barrel’ if the vote is lost;

Nigel Farage will lead a pro-Brexit rally outside Parliament while MPs are voting.

Ministers hope the symbolism of MPs voting on the day the UK was originally due to leave the European Union will pile pressure on opponents of the deal to back down. They also believe the public would blame MPs for blocking Brexit.

Attorney General Geoffrey Cox, who will open today’s debate, said the vote would give MPs the last opportunity to lock in the May 22 departure date and avoid further debilitating uncertainty and delays.

Commons Speaker John Bercow, who had threatened to block a third vote on Mrs May’s deal unless it was ‘substantially’ different, last night approved the vote, saying the decision to split the deal met his test.

But senior Tories acknowledge they face an uphill battle. Mrs May’s DUP allies last night said they would vote against the deal, despite days of frantic negotiations to win them round. And despite Mrs May offering to resign before the second stage of Brexit talks, only a trickle of Tory Eurosceptics have switched sides.

MPs will today vote only on the withdrawal agreement, which sets out the separation terms. They will not vote on the ‘political declaration’, which sets out the Government’s vision for a close economic partnership outside both the customs union and single market. The two documents have previously been bundled together.

Until now, Labour has objected to only the political declaration.

Justice minister Rory Stewart acknowledged that, with a bunch of hardline Eurosceptics dubbed ‘the Spartans’ still holding out, the Government would need the backing of some Labour MPs. He said: ‘What happens depends on Labour. The Labour front bench has said their problem is with the political declaration, not the withdrawal agreement. There is no reason for them to oppose it.’

But former minister Richard Benyon said Tory hardliners also had to face the reality that if they continue to reject the deal they will face a soft Brexit – or risk not leaving the EU at all. He added: ‘They need to recognise that there will be a softer Brexit if they don’t help get this through. And tough on them, frankly.’

Mr Duncan Smith said: ‘ If I believed there was a scintilla of a chance that we could leave the EU with no deal, then I would not vote for Mrs May’s deal today. But the brutal fact is that there isn’t.’

The EU has indicated it is happy for the two elements to be split, with one source saying it was ‘not an issue’. If the withdrawal agreement is passed today, the UK’s exit date would be fixed at May 22. But Mrs May would still have to implement both elements of the deal before then – or risk setting up another No Deal ‘ cliff edge’ in late May.

Whitehall sources acknowledged that the odds are stacked against her winning today’s vote.