Theresa May is heading for a crushing defeat on Brexit vote in the Commons today. Despite a series of last-minute appeals to rebel Tory MPs to back her EU withdrawal agreement.

Senior MPs and a number of sources are predicting a defeat for the prime minister of between 100 and 200 votes, which is likely to be followed by Jeremy Corbyn calling a vote of no confidence in the government.

Mrs May’s allies insist that whatever the scale of the defeat, she has no intention of quitting or calling a general election, but she will come under enormous pressure to unveil a Brexit Plan B.

On the eve of the historic vote, the prime minister appealed to MPs during a Commons statement to take a “second look” at her agreement, despite admitting it was not perfect and was a compromise.

In the Commons, she said: “It is not perfect but when the history books are written, people will look at the decision of this House and ask, ‘Did we deliver on the country’s vote to leave the EU, did we safeguard our economy, security or union, or did we let the British people down?'”

Then, in an emotional speech to Conservative MPs that was described by her supporters as a “bravura performance”, she urged them to “keep Jeremy Corbyn as far away from No. 10 as possible”.

Theresa May, the Prime Minister CREDIT: LEON NEAL /GETTY IMAGES EUROPE 

Winding up day four of the five-day Commons debate on the withdrawal agreement in the early hours of the morning, the chancellor Philip Hammond told MPs: “We as a House now need to move swiftly and decisively to get behind the deal.

“To make the tough choices that are needed to simultaneously deliver the Brexit people voted for, to protect our economy and our national security and to give them the brighter future they were promised.”

Too little too late

Despite delays by the government, the Brexit deal faces a similar parliamentary arithmetic to the one it did before. The prime minister had promised she would secure additional “legal and political assurances” from Brussels when she delayed a vote on her deal and fought off a challenge to her leadership. However, weeks after and nothing changed. Her vote still faces stiff opposition from the labour party and Tory rebels are set to defy whips and vote against the deal today.

What happens next?

If the deal is rejected by MPs, Mrs May has three sitting days to return to Parliament with a “Plan B”.Some have suggested she would head to Brussels on Wednesday to try to get further concessions from the EU, before returning to the Commons to give a statement about her new proposal by Monday. This could then be put to a vote by MPs.

If this also fails, there is a proposal put forward by senior Conservative backbenchers Nick Boles, Sir Oliver Letwin and Nicky Morgan for a “European Union Withdrawal Number 2 Bill”. This would give ministers another three weeks to come up with another plan and get it through Parliament.

If this doesn’t work either, they propose giving the responsibility of coming up with a compromise deal to the Liaison Committee – which is made up of the chairmen and chairwomen of all the Commons select committees, drawn from opposition parties as well as the Conservatives.

This proposal in turn would have to be voted through by MPs.