Scottish Green co-leader and Government minister Patrick Harvie could face a confidence vote in Holyrood.
The Alba Party announced on Tuesday its Holyrood leader Ash Regan is submitting a motion of no confidence in the minister, which could force a vote he would almost certainly win.
The motion comes over Harvie’s failure to say if he accepts the findings of the Cass Review in an interview on Monday.
Asked five times if he accepts the report, the minister refused to say, instead claiming it has been “politicised and weaponised” against trans people.
The review – published earlier this month – highlighted a lack of evidence for some treatments of transgender young people and decried the “toxic” debate around the issue.
The motion would require support from 25 other members in Parliament before it could force a vote, but the joint numbers of the SNP and Greens would likely be enough to save Harvie’s job.
Ms Regan – who defected from the SNP to Alba last year – said: “The motion of no confidence speaks for itself. The Scottish Greens wish to side with ideology over clinical evidence.
“I am hopeful that MSPs will put good governance first, ahead of party lines, and support the motion.”
The motion creates an awkward position for some SNP MSPs who are known for their gender critical stance and antipathy to the Greens.
Fergus Ewing was suspended from the party’s Holyrood group for a week after voting for a similar motion to sack Green co-leader and Government minister Lorna Slater, meaning disciplinary action could be taken against those who defy the SNP whip this time round.
The motion comes as a senior SNP MP backed the powersharing deal between the two parties.
Alison Thewliss, the MP for Glasgow Central, said the Bute House Agreement “has brought the best of our parties and the best of our policies together”.
Speaking on BBC Radio Scotland on Tuesday, she said: “I very much supported the Bute House Agreement.
“I think the partnership with the Greens has brought the best of our parties and the best of our policies together and I would support it staying.”
Asked if she believes SNP members should be given a vote on the deal, she said: “From the SNP members I’ve been speaking to over the weekend, I don’t perceive a huge groundswell of people calling for that.
“That may be something we wish to consider, but certainly I support the Bute House Agreement and I think that has been a positive thing.”
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