SCOTTISH Green co-leader Patrick Harvie has intervened in the SNP leadership contest just 24 hours after saying he would stay out of it.

Mr Harvie demanded the next first minister commit to a “watertight ban” on gay conversion therapy after Kate Forbes was questioned about it on Monday night.

In a Sky News hustings, the Finance Secretary said she considered the practice “abhorrent” but stopped shoprt of saying she would ban it outright.

Asked if a gay adult man should be allowed conversion therapy, Ms Forbes said: "Well, it's his choice. but I do not think we should allow conversion therapy.”

Her comments produced a backlash on social media from supporters of her main rival, Humza Yousaf.

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Mr Yousaf is the only one of the three candidates committed to maintaining the 2021 Bute House agreement between the SNP and Greens to run a joint government.

At 5pm on Monday, Mr Harvie said: “The Scottish Greens are clear that the SNP leadership is a matter for their members, and their members only, and rightly so.

"We will not seek to influence it. We will discuss the results and its implications as soon as it is known."

However today, in a clear nod to Ms Forbes’s comments, he issued a statement condemning gay conversion therapy, saying it was always coercive, never a choice.

The Glasgow MSP, who owes his ministerial position to the Bute House deal, said: “Anti-LGBTQ+ conversion practices are abhorrent and abusive by nature. There is no such thing as a non-coercive conversion practice and never can be.

“Anyone who argues that people should be able to consent to this form of abuse is clearly failing to understand the issue.

"Nobody should be told that they are not good enough or that they should be ashamed of who they are.

"The Bute House Agreement between the Scottish Greens and the Scottish Government committed to a watertight ban on all conversion practices. That is what we believe in and is the commitment we would seek from any new First Minister. 

"Anything less than a full and unequivocal ban would go against that Agreement, which was overwhelmingly supported by the membership of both parties.

"Equality is, and always will be, central to our party and our vision for Scotland."

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The Bute House deal does not in fact commit the SNP and Greens to a “watertight ban”. The text is more ambiguous.

It says the two parties will “aim to bring forward legislation to implement a ban on conversion therapy in Scotland, which is as comprehensive as is possible under currently devolved powers by the end of 2023, unless sufficiently comprehensive proposals are brought forward before then by either the UK Government or through the Scottish Parliament”.

The Scottish Greens were asked how Mr Harvie's comments today can be reconciled with his promise on Monday not to seek to influence the SNP contest.

A spokesperson replied: “A watertight ban on conversion therapy in all its forms is both Scottish Greens policy and a commitment of the Bute House Agreement.

"We have reiterated that today to reassure members and supporters our views have not changed in light of heightened media interest and should be viewed in that context.”