Beth Rigby, deputy political editor

Theresa May faced a choice last month after her EU exit deal was voted down in record-breaking style by MPs. Should she dilute some of her own red lines to find a way through the Brexit impasse by working with opposition MPs, or stick to her guns and try - again - to win over her mutinous Brexiteers?

In the flurry of talks that took place in Number 10 in the days after that defeat, the prime minister made her choice: this dyed-in-the-wool Conservative put the unity of her party above all else.

For all the soaring rhetoric of acting in the "national interest", in the end Mrs May's survival instinct kicked in; she would bend to her Brexit ultras' demands.

"She's finally realised the only votes that she can get through are on her side and everyone else wants to just destroy her," said one senior Brexiteer, who voted for the prime minister to start fresh talks with the EU over Britain's draft exit treaty.


They have supported her on the condition that she come up with "alternative proposals" to the Irish backstop, which aims to avoid a hard border on the island of Ireland by setting up a temporary customs union between the UK and EU.

But don't be fooled by this apparent reunification of the Conservative Party. It was less that two months ago that Brexiteers staged a confidence vote in their prime minister: riding in behind her now is what I would describe as very qualified support indeed.

It was less that two months ago that Brexiteers staged a confidence vote in their prime minister: Riding in behind her now is what I would describe as very qualified support indeed.

For this is a Faustian bargain between a prime minister who feels she must at all costs deliver the Brexit she's promised and a subset of her party that wish her gone.

They are already commanding a high price for their support, with the hardliners demanding treaty change - what many dub the unicorn option - as No 10 works behind the scenes for something more realistic like extra legal guarantees to assuage concerns.

Mrs May knows she won't be able to win some Brexit ultras around. Her ministers instead work on those who might be biddable, with the DUP regarded as the key that could unlock a compromise and bring over votes.

But even if she can get the deal through, Brexiteers' support will not continue much beyond 29 March. Rebels are adamant that she cannot be the one who leads the future trade deal talks.

For those who voted Leave, she is a sheep in wolf's clothing, trying to trick them into a Brexit that will tie the UK forevermore into a customs union with the EU, unable to strike free trade deals around the world. Britain will remain a nation orbiting the very superstate we were meant to escape.

As the clock runs down, and the prospect of no deal looms larger, the pressure will grow on her MPs to back Mrs May's deal. But they might well demand her orderly exit from Downing Street in return for giving her an orderly exit from the EU.

"There is no doubt a feeling amongst us that she has got to go and got to go soon," one MP told me this week. "She simply can't stay on after this," said a normally mild-mannered MP. "We've lost all respect for her."

Of course, Mrs May could well enjoy a Brexit bounce if she manages to deliver what at times has felt impossible and get Britain out of the EU, with a deal, on 29 March.

But her premiership carries with it wounds of Brexit warfare too deep to plaster over. Even if she wins this battle, the knives will remain unsheathed. Held hostage by her Brexiteers, they will want to kill her off before the year is out.

Every Tory leader since John Major has moved to placate Eurosceptic MPs only to discover it is never enough. Mrs May will hope on this occasion she can get her deal over the line, but don't doubt for a minute that her Brexiteers won't extract a high price: Brexit means Mrs May's exit.

Sky Views is a series of comment pieces by Sky News editors and correspondents, published every morning.

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