The Scottish Tories leader has been quizzed about the ex-foreign secretary, who is being billed as a leadership challenger with Theresa May having already forecast an end to her prime ministerial term.

Ms Davidson, who has urged Scots to “stand up against” Nicola Sturgeon’s push for independence in tomorrow’s European elections, said she would give the same consideration to any candidates for the UK’s top role, including Mr Johnson.

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Asked if she could work with Mr Johnson if he won the leadership race, Ms Davidson told the Scottish Daily Express: “I have worked with him when he was foreign secretary.

“I will work with whoever the Prime Minister is.”

Ms Davidson added: “I haven’t had a phone call yet to ask me to run his campaign in Scotland. I am not expecting the call.

“But I will genuinely judge him on the same criteria as I judge any of the candidates.”

The Scottish Tories leader insisted she wanted to see as many candidates for the leadership as possible.

She suggested the coronation of Theresa May in 2016 when Andrea Leadsom pulled out of the race to become Prime Minister had been to blame for some of the party’s “issues” since then.

“There wasn’t the testing of them both under pressure, under campaign conditions, and all of the things that you learn from that,” she said.

Ms Davidson again called for compromise among the Tory and Labour backbenches to push through a Brexit deal.

“We know that the SNP won’t back any deal,” she said.

“They want to sink Brexit. Nicola Sturgeon has already said there’s not a thing that will come to the House of Commons that her MPs will back. She is just a wrecker in all of this.”

The Brexit Party is forecast to win as much as 34 per cent of the UK vote in tomorrow’s European elections.

But Ms Davidson dispelled suggestions Brexit Party leader Nigel Farage was likely to be a long-term threat, pointing towards his seven failed bids to enter the Commons.

“People know Nigel Farage on the European question,” she said.

“Whether he can break out of that, whether the Brexit Party named after Brexit can break out of that, I am not too sure.

“While I wouldn’t discount it, he’s a political operator who has learned over the years and clearly at the moment is well funded and has a well-oiled machine behind him. I still think the electorate will need to see a bigger offer for it to translate to the Commons, local authorities and particularly in Scotland.”

The Scottish Tory leader warned failing to abide by the result of the 2016 vote risks the public’s faith in democracy.

Ms Davidson questioned how pro-union politicians could oppose a second Scottish independence referendum if they backed another EU ballot.

Her comments come a day after Mrs May announced she would offer MPs a vote on whether or not to hold a second Brexit referendum in a bid to get her Brexit Withdrawal Agreement Bill through Parliament.

Writing in the Scottish Daily Mail, Ms Davidson said: “If we really do respect democracy in this country then political parties should try to accept the need to deliver Brexit as promptly as possible.

“The failure to do so has, justifiably, sparked a backlash in Scotland and right across the UK.

“We must listen. I’m utterly clear in my mind that we should abide by the result of the 2016 referendum or risk faith in that democracy withering on the vine.”

She added: “I also fear the precedent that a second EU referendum would set if we do not.

“How can pro-union politicians like me credibly oppose indyref2 if our position is to back another EU referendum?

“I voted No and Remain in these polls. But how can you demand a rerun of a referendum result you lost, but insist the one you won is upheld?”

SNP leader Nicola Sturgeon highlighted the apparent division at the top of the Tory party on the issue of a second Brexit referendum.

She tweeted: “The PM might not have guaranteed a second EU referendum, but her promise of a vote on one puts the Scottish Tories ‘vote for us for no more referendums on anything ever’ pitch on something of a sticky wicket. Just an amusing aside.”

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