RUTH Davidson is coming under pressure from senior members of her Holyrood team to break away from the UK Conservatives if leading Brexiteer Boris Johnson becomes Prime Minister.

One Tory MSP spoke of his horror at the prospect of the former London mayor taking over as PM in the event of a Leave win.

Asked by The National what would happen if Johnson came to power, he said: “I think the sky would fall down!”

He added: “If there is a vote to leave the EU, which I’m hoping there won’t be and I don’t think there will be, it would be indicative that the leadership in Scotland is stronger and more pragmatic than it might be in other places.

“The Scottish Conservative Party has an extremely strong leadership at the moment and that leadership will prevail. I think progressively we will see a more [autonomous party] in Scotland and I think it’s being driven by the fact that under devolution we operate in a very different environment and consequently require a different approach.”

The MSP spoke out after a newspaper article yesterday claimed Davidson – whose party overtook Scottish Labour to become the main opposition at Holyrood last month – was preparing to split from the UK Tories and lead her party under a new name in the event of Johnson replacing David Cameron as Prime Minister.

The report cited a source close to Davidson claiming she would “do a Murdo” and establish a new, right-of-centre party in Scotland if Johnson replaces David Cameron in the aftermath of the European referendum.

The comment to “do a Murdo” refers to MSP Murdo Fraser’s previous call for the Scottish Conservatives to break away from the UK party and form a “new party for Scotland” – a proposal which was at the heart of his campaign against Davidson for the party leadership in 2011.

A Scottish Conservative spokesman dismissed the story yesterday, saying there was “no substance to this whatsoever”.

“We have just achieved our best-ever result in a Scottish election, proving that we can win in Scotland as Conservatives,” he said. “Our entire focus is on being the strong opposition Scotland needs.”

However, the newspaper insisted the story was accurate and said it stood by its source.

Remain supporter Davidson, who last night faced Johnson in a televised EU debate in London, has made no secret of her differences with Brexit figurehead Johnson.

In March she launched a scathing attack on the Tory MP after he appeared on the BBC’s Andrew Marr Show.

During his 25-minute grilling, Johnson struggled to make clear how he envisioned Britain’s future outside the EU as he denied the suggestion he was only backing Brexit to improve his chances of succeeding Cameron as Prime Minister.

“Is it just me or is Boris floundering here? Not sure the bumble-bluster, kitten smirk, tangent-bombast routine is cutting through,” Davidson wrote on Twitter.

A second Tory insider said last night that the issue over the party’s future structure was unlikely to go away.

“I have no doubt this story is accurate, but the person I feel sorry for in all this is Murdo Fraser. He was the one who campaigned for an independent right of centre party in the 2011 leadership contest,” he said. “Ruth’s platform was that she was against that and now all of a sudden we are back to square one.”

In a blog post for Conservative Home yesterday, Davidson adopted a conciliatory tone about the way the aftermath of the referendum should play out for her party north and south of the Border.

She wrote: “I hope that a degree of leadership from those who want to bind us back together can be replicated at all levels in our party, that the mutual support and benefit we derive from working together in different parts of the country is enhanced, not diminished.”

Voters go to the polls tomorrow to decide whether the UK should stay in or leave the EU. Opinion polls show the two sides are neck and neck, though two of the most recent surveys suggest the Remain camp is slightly ahead. The result is expected on Friday morning. savaged over 'Project Hate' EU referendum campaign during TV debate. 19098