A referendum is the only legitimate route to an independent Scotland, Scottish Greens co-leader Patrick Harvie said today.
Speaking after he was re-elected as co-leader of his party today, Mr Harvie said a pro-independence majority in the Scottish Parliament after the next Holyrood elections would be "enough to say there should be a referendum" but he stressed "a referendum is the only mandate for independence."
Several SNP politicians have recently claimed Scotland could become independent without the granting of a Section 30 order from the UK government to hold a referendum, as a "direct mandate" for constitutional change could come from the SNP winning a majority of seats at Holyrood.
Mr Harvie said: "I don't think any political party should say if we win an election, Scotland should become independent. But I think that any UK government that explicitly rejected the democratic mandate of the Scottish Parliament to hold a referendum would be showing utter contempt to the people of Scotland."
He also said there was nothing to stop the Scottish Government opening independence negotiations with the UK government at any time, but doubted "a UK government would be willing to negotiate it unless there had been a clear and explicit referendum mandate."
And he said he was sceptical about Prime Minister Boris Johnson's refusal to agree a second vote should be held. "Of course everybody believes every word that comes out of Boris Johnson's mouth, he's a very principled and honest person yes?
"Boris Johnson is not someone who can be expected to be consistent on this, even his predecessor Theresa May said there was no way there'd be a snap election and then she called one. Things can change very quickly. In particular, with the push for a border poll in Northern Ireland as well, I think it's very clear that people, especially in parts of the UK who voted Remain, are not going to be willing to have this disaster capitalist project forced upon them."
He also claimed that the case for a second independence vote was "very strong" and would be more so "if there is a crashing out of the EU without any deal at all, because we know how much that will damage not just our economy, but our society, peoples rights and protections in terms of the environment and food standards - a huge amount will be put at risk.
"I think there will be another independence referendum and I think the arguments will be far different than they were in 2014 given the catastrophic mismanagement we've seen from the UK government with its hard right Brexit agenda, but when it will happen I don't think anyone genuinely knows when - anyone who gives you a firm prediction on that is winging it.
"People in Scotland have voted by different percentages for both unions. If they're not going to be allowed what they voted for, they need to have a final say in which is the most important to them. I think the opportunity to be an independent European Union country is the future path Scotland will ultimately be on.
"The idea that we go through this Brexit process and every other EU member state gets a say, the UK government gets a say, the European Commission gets a say but the people of Scotland are politically unable to determine their own future is unacceptable."
Asked if the Scottish Greens would campaign with the SNP in any future referendum, as they had in the 2014 Yes campaign, he said: "If we're in a process like that, or in another EU referendum, we will want to work with others where we have common ground but we will absolutely have a responsibility and an eagerness to set out a distinctive Green stall on those issues as well.
"We took part in the Yes campaign, not just with SNP but others the last time, and I think everybody would recognise there are lessons to be learned from that, after all we didn't win. At the same time we ran a Green yes campaign that was very distinctive which challenged the SNP on oil, on currency union and NATO membership and I think that voice was important in broadening the appeal of Yes."
Mr Harvie's new co-leader is Lorna Slater, a Canadian tidal energy company project manager, who has previously stood unsuccessfully for the party in council, Westminster and Holyrood elections. She replaces Maggie Chapman.
Ms Slater who has lived in Edinburgh since 2004, said she was a "surger" after joining the Scottish Greens in the wake of the 2014 referendum. "I have always been a Green voter and wanted to get involved in politics but before that I thought the Greens were not a significant force but when Green Yes happened they were everywhere and a political force to be reckoned with and I thought this is worth giving my time to. It's going to matter and make a difference."
She said her role as co-leader was to get more women into the Scottish Parliament. "Five of our lists will be headed by women and one I hope will be me, and if I'm one of those women great, but if not my job is to get them elected," she said. "Our women's network had become defunct but we're relaunching that. Last time most of our women candidates didn't win because they weren't well supported that's going to change this time."
Mr Harvie said the party was already gearing up for the 2021 elections, with candidate selections already underway, and he criticised the Scottish Government as being "lacklustre".
"Whatever the catastrophic incompetence we're seeing from the UK government we're also seeing some lacklustre government in Scotland as well and there's an appetite for a more transformational agenda," he said.
"What we've seen, particularly in last few months, is an opportunity for the Scottish Parliament to go further on things like land reform, on fairness and justice in the planning system, on regulating damaging industries like the short term lets industry which is having a wrecking effect on communities, and the government has simply not gone with us on these issues and I think that clearly states that we need more Greens in parliament and on councils too."