THE Scottish Greens would have to resolve "challenging issues" with the SNP if they are to enter into a formal coalition, Patrick Harvie has said.

The party co-leader gave an indication of the Greens’ red lines over a potential deal with the next Scottish government.

He insisted the decision would be for the members – not just himself and fellow co-leader Lorna Slater – to decide whether the party should enter a coalition with the SNP if that is an option after the May 6 Holyrood election.

His comments came as a new opinion poll suggested the SNP will fall short of the number of MSPs needed for an overall majority.

Harvie said there are a number of issues that might make a formal deal between his party and Nicola Sturgeon's SNP difficult, even though they both support Scottish independence.

He cited "challenging issues" around taxation, fossil fuels and transport during an interview on BBC Radio Scotland's Good Morning Scotland programme.

"Greens are in government in a number of countries, there is nothing wrong with aspiring to being in government, every political party does,” Harvie said.

"It is for the public to decide what the result is, and I don't want to second guess the result. We're working hard for the final two weeks of the campaign to convince people that a Green vision for Scotland is the future.

"And it will be for the largest party, and if the polls are right that will be the SNP again, to decide whether they want to form a minority government or work with others.

The National:

READ MORE: Two new polls predict pro-independence majority at Holyrood election

"It would be a democratic decision for our members to take, it wouldn't be for myself and Lorna as co-leaders to take, we're not that kind of top-down party.

"I suspect a lot of our members would be willing for us to have the conversation, but I think there would be a really challenging issue around taxation policy, around oil and gas policy, and around a lot of those transport policies that have been going in the wrong direction."

He pointed out that the Greens have won concessions from the SNP Government over the last five years in return for supporting its budgets, which "demonstrated that if an opposition party treats its job seriously, and focuses on putting forward good, positive, constructive ideas to make life better for people in Scotland instead of scoring cheap political points, you can get results".

Meanwhile, the Greens co-leader insisted the emergence of the pro-independence Alba Party is not a threat to his party.

He commented: "I'm very clear that the decisions in this election, and the decisions in a future independence referendum, are about Scotland's future.

"They're about how we address the climate and nature emergencies, Scotland has been missing its climate targets repeatedly as a large result of government action on transport, which has allowed emissions to rise not fall.

"We have chronic poverty and inequality in our society, we have to restore the position in Europe and build a relationship with the wider world.

"I don't see Alex Salmond as the answer to any of those questions about the future and I think there's very little overlap between the kind of people who are attracted to the positive Green vision for Scotland's future and those who are harking back to yesterday's men."