HUMZA Yousaf today told a party hustings that if one of his rivals won the SNP leadership contest and then tried to end or revise the deal with the Scottish Greens they may not get to become First Minister.

The Scottish Greens have previously refused to discuss what they would do if the winner of the SNP contest wanted to end or revise the Bute House Agreement.

The final party hustings, the third this weekend, was calmer in tone than last Tuesday's STV debate but it also saw the three candidates differ on a range of policy issues most notably the future of the Bute House Agreement.

Both finance secretary Kate Forbes and former community safety minister Ash Regan have suggested they may want to revise certain areas of the deal. 

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Ms Forbes has said economic prosperity (the Greens do not support the principle of economic growth, which is excluded from the shared policy areas in the deal) may be one area that would have to be reviewed.

The deal was signed in August 2021 and saw the Greens join the government with two ministerial roles in return for supporting the SNP on key votes in Holyrood such as the Budget and confidence votes.

Throughout his campaign Mr Yousaf has warned of what the believes are the consequences for smooth government of the deal breaking down.

But during the Aberdeen hustings this afternoon he went further suggesting if the Greens walked away from the agreement, the winner of the SNP contest may struggle to get parliament's backing to become FM. 

"Can you imagine trying to pass legislation or budget after budget relying on Douglas Ross or Anas Sarwar. You are right to laugh because it's preposterous," he told SNP members.

"You would not get far at all. Truly presenting ourselves as a unifier, the first thing you can't do is then reject the second largest pro-independence party in the country. You can't do it. So for me this idea you can go in and negotiate and rip it up or set the terms. 95 per cent of our membership endorsed it. So we should listen to that membership.

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"If we go in there and demand that we unpick the deal, I am telling you what the response from the Greens is likely to be. And then you have to remember the very first thing we have to do is on Monday 27 [March] you will know who your leader is."

He added: "On the Tuesday the parliament will have to vote for them. If you boot out the Greens - good luck. Good luck on getting yourself nominated as First Minister."

Ms Forbes - who polls suggest is the public's preferred candidate to win the race - said "in principle" she recognised that the Bute House Agreement "makes governing a lot easier". 

However, she added: "One of the issues that I've put front and centre though in my campaign is ensuring that we really are delivering economic prosperity, not prosperity as an end in and of itself, but prosperity with a purpose as a primary means of eradicating poverty. 

"Because prosperity creates wealth, secure jobs are a key route out of poverty, and also raise the revenues that we need for our public services."

Pointing to economic growth being excluded from the agreement, she added: "So I think there is scope to continue to work together.

"The question would be in the event that I was successful, of sitting down and saying, look, this is where I think we really need to ensure we're tackling the cost of living crisis, we're raising the revenue for our NHS through economic prosperity, and then have that conversation with the Green Party."

She added a prosperous economy was needed in order to tackle the cost of living and raise revenue for the NHS - voters top priorities.

Ms Regan said while the Scottish Greens while important to the independence movement and to the government, there were areas in which the two parties did not agree.

She cited differences on the speed of the transition away from oil and gas as well as on road building projects such as the dualling of the A9.

"The way forward with this is to say that I would be open to working with the Greens, continuing in government with them, but obviously any government that we are running for Scotland needs to reflect the priorities of the people of Scotland, and to protect and grow our economy, our infrastructure and protect jobs. 

"So if the Greens are on board with that I'd be very happy to continue working with them, but equally, if that is a sticking point for them which it may be, I would be equally happy to run a minority government instead."

But following today's hustings Mr Yousaf's claims were dismissed as "very unlikely" and "nonsense" by some Labour figures on social media.

Scottish Labour activist Duncan Hothersall said: "Not only is this not true, Humza Yousaf knows it's not true. He's suggesting the Greens would ally with the Tories, Lib Dems and Labour around a shared single candidate for FM. To call that very unlikely would be a huge understatement. Who would they all back, Douglas Ross?"

Labour leader or Inverclyde Council Stephen McCabe wrote on Twitter: "What is [Humza Yousaf] claiming, the Greens would unite with all the other parties to tie the vote at 64-64? Who would be the combined opposition candidate? He's talking nonsense of course..."

The ballot in the SNP leadership contest opens tomorrow and continues until March 27 when the winner is expected to be announced.