The former community safety minister issued a “call for calm” to Humza Yousaf and Kate Forbes as tensions rose in the race over Ms Forbes’ comments on social issues.

The Finance Secretary has come under scrutiny from party members and the wider public for her views, losing many of her most high-profile supporters after saying she would have voted against same-sex marriage legislation and that having children outside of marriage “would be wrong according to my faith”.

Ms Forbes is a member of the Free Church of Scotland.

Asked about his opponent’s comments Mr Yousaf – a practising Muslim – told Times Radio he would not use his faith as a basis for legislating, adding he believes in a Scotland that “celebrates differences, celebrates diversity, celebrates equality”.

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Deputy First Minister John Swinney also waded into the controversy, telling the BBC on Wednesday he “profoundly” disagrees with Ms Forbes despite his own “deep faith”.

Speaking to STV News on Wednesday, Ms Regan said: “I just want to put out a call for calm – I think that’s really important at the moment.

“Kate and Humza are really valued colleagues, they’re a really important part of the SNP.

“So, I think all the mudslinging that’s been going on just now just needs to stop, everyone needs to take a breath.

“We’ve all got to remember that we’re all going to be working together at the end of this.

“I want us all to come back together as a strong SNP and we’re all going to be working together for the betterment of Scotland.”

The Edinburgh Eastern MSP’s comments mirror those of her supporter and senior SNP MP Joanna Cherry, who urged a senior party official to “call the dogs off” in relation to Ms Forbes.

In the hours before Ms Regan’s call for calm, transport minister Jenny Gilruth announced her support for the Health Secretary while taking a veiled swipe at Ms Forbes.

She said in a video posted to Twitter that Mr Yousaf would be a “first minister who would defend my love for my wife” and “will defend the Scottish Parliament unequivocally” in reference to Ms Forbes and Ms Regan saying they would not fight the UK Government’s blocking of gender reforms.

Meanwhile, Scottish Secretary Alister Jack told MPs there was a “real opportunity” for the new first minister to “reset the relationship” with the UK Government.

Opening Scotland questions in the House of Commons, Mr Jack said: “I realise many of my colleagues on the (SNP) benches diagonally opposite are somewhat preoccupied by the contest to become the leader of the SNP and Scotland’s first minister.

“In my view, this is a real opportunity for a new first minister to reset the relationship with the United Kingdom Government, to work constructively with us and to make life better for the people of Scotland.

“We need a first minister who will put Scotland’s interests above the nationalist interests and my offer to all those running in this is that the United Kingdom Government stands ready to work with you and that will be the real win for improving the lives of people in Scotland.”

SNP MP Martin Docherty-Hughes (West Dunbartonshire) jokingly thanked the “governor-general” for a “long-winded” reply to his question linked to retained EU law.

Scotland minister John Lamont joked during the Commons session that the SNP had “decided to provide the country with compelling drama now that Happy Valley has ended”.

Labour shadow Scotland secretary Ian Murray claimed it was “frankly absurd that failed Scottish government ministers are fighting amongst themselves for the top job when too many Scots are worrying about how they pay their bills”.

Mr Murray said: “Scots are being hit very hard by the cost-of-living crisis which is made worse by the state of Scottish public services.

“The NHS is on its knees while the failing Health Secretary is focusing on other things and Scottish local government is having its funding decimated again by the finance secretary seemingly intent on offending every minority group in Scotland.

“So does the minister agree with me that amid such a serious crisis in Scotland, it’s frankly absurd that failed Scottish government ministers are fighting amongst themselves for the top job when too many Scots are worrying about how they pay their bills?”

Mr Lamont replied: “It does seem that the SNP have decided to provide the country with compelling drama now that Happy Valley has ended, but there is a very serious point here.

“Whilst the SNP indulge in the most savage infighting since Labour’s Blair/Brown civil war, Scotland is crying out for attention on things that really matter, the economy, the health service and the education system.”

Ash Regan calls for end to ‘mudslinging’ in SNP leadership race amid Kate Forbes storm