THE SCOTTISH Tories are in a toxic civil war over Theresa May’s Brexit deal, with relations between the party’s MPs from north of the Border at an all time low.

While all 13 of the party’s Westminster politicians now back Brexit, three ultra Brexiteers – Douglas Ross, Ross Thomson and Jon Lamont – are holding out, refusing to back the Prime Minister.

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The row intensified earlier this week when 10 Scottish Tory MPs wrote to the Times newspaper, urging their three colleagues not to vote down May’s deal as it would risk “turbocharging” Nicola Sturgeon’s campaign for independence.

The letter signed by MPs, including David Mundell, Paul Masteron, Kirstene Hair and Alister Jack, claims a defeat for the Prime Minister’s deal could lead to a second referendum on Brexit, which, in turn, could “empower the separatist cause”.

The National:

The 10 MPs say another vote on Britain’s membership of the EU would “undermine faith in the democratic principles this country abides by and would stoke terrible division – once again putting us all in two opposing camps at a time when we should be coming together”.

It would also, they add, have “the unintended consequence of putting at risk our precious Union”.

“A second EU referendum would empower the separatist cause and strengthen Sturgeon’s plans for a second referendum on independence. No Unionist would want to risk that.”

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In a plea to their three colleagues, the loyalist 10 urge them to act “in the national interest” and “avoid turbocharging Sturgeon’s drive towards independence”.

“That is clearly in the best interests of Scotland and the whole of the UK and we would urge all MPs to support this deal.”

One Tory source told the Sunday National the party risked being “wiped out” if MPs failed to back May.

“This is the best possible deal. It’s the only deal. For these three to pretend an alternative is available is crazy. They’re being reckless.

“They’re not thinking about the country and they’re definitely not thinking about the party. God knows what they’re playing at.”

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MPs were due to vote on May’s Brexit deal earlier this month, but facing a massive defeat in the Commons, the Prime Minister postponed, promising to go to Brussels and seek assurances on the controversial Northern Irish backstop.

The backstop, a safety net in the event of a no-deal Brexit, will see the province effectively remain in the EU, to avoid the need for a hard-border on the island of Ireland. It can only be revoked if both London and Brussels agree.

The assurances May wanted have not been forthcoming and the Prime Minister, yet again, faces near certain defeat when the rescheduled meaningful vote takes place on January 16.

Ross, Lamont and Thomson, who were all MSPs serving under Ruth Davidson before running from Holyrood to stand for Westminster in 2017’s snap general election, were all expected to have rejected May’s agreement at that first vote.

None of them responded to the Sunday National’s request for a comment.

The National:

The SNP’s Alison Thewliss warned all the Tories that their support for Brexit would not be forgotten by Scots voters.

“The fact that three of the 13 Scottish Tory MPs did not sign up to this letter about unity is Tory irony exemplified. The Scottish Tory MPs are about as disunited as the UK Government when it comes to Theresa May’s Brexit deal.

“It’s also pretty rich that 10 Scottish Tory MPs appear to advocate voting for a Brexit deal that will see Scotland at a comparative disadvantage to Northern Ireland and completely disrespects Scotland’s overwhelming vote to remain in the EU.

“The best future for Scotland is as an independent country and the continued efforts of Scottish Tory MPs to peddle a bad deal that will make their constituents poorer will not be easily forgotten.”

Tempers frayed in the group earlier this year when Thomson described some of his colleagues as “arseholes” over their secret plans to kibosh Boris Johnson’s bid to replace May.