SUPPORTERS of Jacob Rees-Mogg have been given plum roles at this week’s Scottish Conservative conference, prompting questions over Ruth Davidson’s hold on her party.

Colin Clark, one of 62 Tories in the European Research Group (ERG), who signed a letter to Theresa May calling for the UK to have “full regulatory autonomy”, will give the welcome address at the event in Aberdeen on Friday. He will be joined to speak on stage by fellow arch Euro-sceptic Ross Thomson, whose name was not on the correspondence sent to the PM last week, but who said he agreed with its contents.

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The views on Brexit expressed in the letter by the group led by Rees-Mogg were at odds with the stance taken by Davidson, who has indicated a “no deal” situation, which could result from the “regulatory autonomy” demand, would be unacceptable. It was also signed by Scots Tory MPs Alister Jack and Stephen Kerr and described as a ‘ransom note’ by Tory MP Nicky Morgan.

Thomson and Kerr have been given top billing at a key session on the economy on Saturday morning, contributing to a discussion on “A Scottish Economy that Works for Everyone”, due to consider how Tory policies could improve jobs and pay.

But earlier this month analyses by both the UK and Scottish Governments warned that under a no deal Brexit the Scottish economy would be severely damaged, with GDP forecast to fall by up to 9 per cent by 2030 - a development that would leave the average Scot £2300 a year worse off.

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Labour’s Ged Killen said the line-up suggested Davidson’s leadership may be vulnerable as Tory Euro-sceptics gained influence.

“Ruth Davidson’s commitment to a soft Brexit is becoming more and more maligned as her own hard Brexiteers take on significant platforms at the Scottish Conservative conference,” he said. “It is notable Colin Clark and Ross Thomson, two signatories to Rees-Mogg’s hard Brexit ransom letter to the PM will welcome delegates. They might not just be welcoming delegates to their seats but to a new direction on Brexit for the Scottish Conservatives. Ruth Davidson once said, referring to Boris Johnson, that ‘nobody is unsackable’. It turns out the hard Brexit-minded Scottish Tories may be taking this to heart - but it is Davidson, not Johnson who may end up in the line of fire.”

The SNP’s Pete Wishart said: “The starring role for the Scottish Tory hard Brexiteers tells us everything we need to know about the current direction of the Scottish Conservatives. Far from being beyond Ruth Davidson’s control they and their hard Brexit agenda are now centre stage...What is almost beyond parody is these hard Brexiteers are the stars of a session called an ‘economy that works for everyone’. We now know from the Government’s own impact assessments the [option they favour] would cost Scotland some £16 billion a year year.”

Lib Dem Christine Jardine said: “The Scottish Conservative conference is turning into a real headbangers’ ball. Ruth Davidson has been desperate to present her Scottish Tories as moderates but the past few weeks have shown otherwise.”

Thomson, MP for Aberdeen South, said the conference would be a platform for his party to show they are ready to govern in Scotland.

“I am very proud the event will be held in my home city of Aberdeen,” he said. “It is only right after a stunning general election result in the north-east, where we now hold six of seven parliamentary seats.

"I look forward to joining my colleague Colin Clark in opening the conference as two local MPs. We are all 100 per cent behind the Prime Minister and the ERG group letter is all about providing more power to her elbow in negotiations. It stays true to the position set out in her Lancaster House speech, which was endorsed by Ruth Davidson as a ‘clear direction’ for a new relationship with Europe.”