NICOLA Sturgeon has accused Ruth Davidson of becoming a “hard Brexiteer”, saying the Scottish Conservative leader is “cosying up to Boris Johnson”.

Her comments at First Minister’s Questions came after Davidson said in an interview that she had previously worked with Johnson when he was foreign secretary and would work with whoever in her party became prime minister.

Davidson has previously repeatedly suggested she is no supporter of the high-profile backbencher, who is open to leaving the EU without a deal and is the Tory grassroots favourite to succeed Theresa May as Tory leader and prime minister.

He was not welcome at the Scottish Conservatives conference in Aberdeen last month and among the many interventions made by him which she has condemned are comparisons he made between women wearing burkas and bank robbers.

Ahead of the UK Tory party conference last year, the Scottish Tories even launched a secret campaign against Johnson to stop him becoming leader.

It was code-named Operation Arse, one senior Tory source said, “so we’d all be clear who we were talking about”.

Referring to Davidson’s change of attitude on Johnson, Sturgeon yesterday accused the Scottish Tory leader of “flip-flopping”.

She said: “The difference perhaps between Ruth Davidson and I is this: I’ve got principles and I stick to my principles. Ruth Davidson wouldn’t recognise a principle. Ruth Davidson used to passionately oppose Brexit, now Ruth Davidson supports Brexit.

“She used to demand that we stayed in the single market, now she wants us taken out of the single market. And Ruth Davidson, of course, used to call Boris Johnson names that I can’t repeat in this chamber – now she is cosying up to Boris Johnson, the arch-Brexiteer.”

She added: “I think we see Ruth Davidson so desperate to cosy up to Boris Johnson today that her conversion to a hard Brexiteer is complete.”

Davidson criticised the First Minister’s call for further referendums on independence and on Brexit.

She said: “This is about demanding more referendums until people are browbeaten into giving her the result that she wants.”

She added: “She talks about principle, well let’s talk about a matter of principle. I believe that if you ask people to make a decision, if you say to people that we will enact whatever you decide, then democracy is fundamentally damaged if at the first opportunity you insist that vote is held again.

“Doesn’t she see that? Doesn’t she see that you shouldn’t change the rules after the event?”

The First Minister questioned how pushing ahead with Brexit would respect the 62% of people in Scotland who voted to remain in the EU. She pointed out that ahead of the 2014 indyref Davidson had told voters that only a vote against independence would keep Scotland in the EU, yet Scotland was being taken out.

Speaking to the Daily Express, Davidson was asked if she could work with Johnson if he wins the race.

She replied: “I have worked with him when he was foreign secretary. I will work with whoever the prime minister is.”

She 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.”

She also insisted the party’s “core vote” appeared to be “holding up reasonably well” – despite the most recent poll suggesting the Tories would come fifth in the UK in today’s elections.

Sturgeon tweeted: “There’s a pattern here. When bad things look unlikely to happen (ie Brexit before the referendum or Boris as PM a few months ago), Ruth Davidson opposes them because it’s safe. But when these things do happen or look likely to, she falls meekly into line. That’s not leadership.”