Conservative MPs remain completely divided on whether Theresa May can win a parliamentary majority for her Brexit deal by wringing EU concessions on the Irish ‘backstop’.
The prime minister has staked her deal on demanding changes to the controversial insurance policy designed to keep the border open on the island of Ireland if trade negotiations drag on or fail.
But the EU is thought to want a clear demonstration that May can build a Commons majority before making concessions that may otherwise prove pointless.
Three MPs, two who backed the deal and one who voted against it earlier this month, said around 300 Tories would swing in behind May if she secured a backstop end date or exit mechanism.
However two Brexiteer sources said a hardcore of around 20 to 60 Eurosceptics could remain implacably opposed to the deal even if the EU relented on the backstop. Another senior Tory MP, who voted Remain, said they could not back the agreement, even with changes.
One minister’s admission to HuffPost UK that they “don’t know what to believe anymore” sums up the challenge the PM faces in persuading Brussels to make significant changes to her deal.
And it came as European Research Group (ERG) chair Jacob Rees-Mogg called on May to prorogue - or suspend - parliament if Remain-minded backbenchers succeed in efforts to delay Brexit, in comments which suggested Leavers still believe they can force a no-deal withdrawal.
The minister summed up the uncertainty gripping Westminster: “People do seem to be more open to changing if the backstop changes. But who knows with this lot.”
One senior backbencher estimated from 10 to 20 Brexiteers and Remainers would remain opposed to the deal but suggested May could count on around 300 Tories plus 10 DUP votes if she got an backstop end date or exit mechanism, meaning only a handful of Labour MPs could get it over the line.
The MP called on the government to table its own amendment next week to try to demonstrate the level of support it could get if the EU made such changes.
One loyalist MP said: “(300) sounds in line with our (wishful) thinking.”
Another added: “I think at least that number but I am sceptical that EU would agree. We should go for it though, very robustly.”
However, a senior Brexiteer source warned there would remain could be “anywhere from 20 to 60 irreconcilables” even if there were changes to the backstop.
These Eurosceptics hate the deal because the UK will hand over a £39bn divorce bill with no guarantee of a trade deal, and because it will mean an indirect role for the European Court of Justice (ECJ) after Brexit.
One senior Tory said they would still vote against the deal and predicted they would be joined by “loads” of colleagues in the ‘no’ lobby.
They described estimates that 300 Tories could be won over as “government propaganda”.
It came as Rees-Mogg called for clear, legally binding changes to the backstop in the Brexit withdrawal agreement as the price of his support, despite EU opposition to reopening the painstakingly negotiated text.
“As long as the backstop is there I will not vote for this deal. I think people’s chances of stopping Brexit are very slim.
“Of course any deal would be better than not leaving at all, but this deal ... is not good enough. It needs fundamental change.”
He said that he believed that “things are going our way”, adding: “We are not there yet.”
Rees-Mogg said everyone wanted a deal to leave “in the best possible way” but that he was on alert for “meaningless soft soap” concessions from Brussels.
“If the only way to get it (a deal) is by reopening the text, that is what they will have to do. This is ‘realpolitik’.”
And he dismissed suggestions the ERG should back May’s deal as the hardest Brexit on offer thanks to efforts by Remainers to hijack parliamentary process to block no-deal.
“If the House of Commons undermines our basic constitutional conventions then the executive is entitled to use other vestigial constitutional means to stop it,” he said. “By which I basically mean prorogation.”