Patrick Harvie said the “trust is broken” between the Greens and SNP after Humza Yousaf ended their power-sharing deal as the party urges him to step aside.
The Greens have indicated they will not be changing their minds about supporting the upcoming motion of no confidence in him – saying he must face “consequences”.
Speaking to STV News, the party’s leader said the First Minister’s decision to end the Bute House Agreement last week was a “serious mistake” and “deeply damaging.”
Votes on the motions of no confidence are expected to take place at Holyrood in the coming week, with the First Minister fighting for a knife-edge vote to save his political future.
Harvie confirmed he had received the letter from Yousaf, sent to leaders of all opposition parties on Friday, in an attempt to build bridges and establish how they can work with his minority government.
Harvie told STV News: “[It] was a serious mistake – bad for Scotland, bad for him and bad for the Government.
“It’s very clear that Humza’s individual decisions – decisions he made, rather than the nature of the SNP government – that’s where the problem lies.
Getty Images“He has broken trust and abandoned a promise to work together in a constructive way. I think that is deeply damaging.”
Harvie said it is the SNP’s responsibility to offer a stable minority government – and he believes Yousaf is no longer “in a position to make it happen.”
“I don’t think Humza Yousaf is able to do that anymore,” he said.
“I think the way for him to avoid either losing or just scraping through a vote of no confidence is to step aside now and allow a first minister to come forward who can bring the majority of parliament with them.
“He or she can only do that with trust. Humza Yousaf, I’m afraid he can’t.”
It comes as Alex Salmond’s Alba party say they will make “reasonable” demands in order to back Yousaf as the crunch vote looms.
The former first minister’s only MSP at Holyrood, Ash Regan, now appears to hold the decisive vote in the no confidence motion put forward following the collapse of the Bute House Agreement.
The tight parliamentary arithmetic at the Scottish Parliament, where the SNP have 63 out of 128 voting MSPs, means former SNP leadership candidate Regan’s support may be needed to get Yousaf over the line.
In the case of a tied vote, the presiding officer would vote to retain the status quo.
Regan will meet Yousaf this week to set out the political price for her support.
Harvie believes Yousaf staying in his position on such a “knife edge” will cause further “chaos and drama.”
“If the current First Minister decides to try and struggle on, I think it will lead to more instability,” he said.
“He might just manage somehow to scrape through, perhaps even on a knife edge, equally balanced vote.
“I don’t think that gives stability the government needs.
“I think it would be a pretty hellish experience for him as a human being and I don’t wish that on him.
“That kind of scenario will just lead to knife edge after knife edge, chaos and drama, almost for its own sake.”
Harvie said the Greens are “ready to work constructively” as an opposition party – but there will be no attempt to recreate the pact.
He added: “I don’t think the trust exists for anything remotely approaching that for the foreseeable future.
“It’s too late for that.”
When asked whether Greens could work alongside Kate Forbes, Yousaf’s former rival in the leadership contest and a potential contender, he said it would be a mistake for the SNP to “lurch to the right.”
He said: “To go for someone who is economically and socially conservative would be a further, deeply serious mis-step.
“There are clearly some on the right wing of the SNP who are less able – not just to work with us, but to bring together the majority of the parliament. Even less so than Yousaf.
“I appeal to those in the SNP to look among their members and decide who is best placed to bring that majority together.”
A Scottish Government spokesperson said: “As the First Minister has said, over the past year he is proud to have laid the foundations of his vision for Scotland.
“The Scottish Government is investing record amounts in our NHS – ensuring it can employ record numbers of staff, deliver the best performing A&E units in the UK.
“Scotland is the only part of the UK to avoid pay-related strike action in our NHS.
“The Scottish Government has delivered a council tax freeze this year in every local authority – helping families where we can with the cost of living.
“Scottish Ministers have removed peak fares on our railways.
“And this month the government approved plans for Europe’s largest floating offshore windfarm.
“Average earnings in Scotland are forecast to grow faster than the rest of the UK.
“Attainment is at a record high, and record numbers of students from deprived areas are entering university.
“And Scottish Government policies are lifting an estimated 100,000 children out of poverty this year.”
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