Speaking during First Minister’s Questions, he told Ms Sturgeon it is now time to “make a judgement” on the issue as he slammed the Brexit deal agreed by the Prime Minister.
The pro-independence Greens and SNP have already combined to vote through a motion demanding a second referendum at Holyrood.
And Mr Harvie said today: “There is already surely enough clarity to make a judgement.
“There’s nothing in Theresa May’s plans that protects the social, economic and workplace rights that we have.
“Nothing that protects the environmental rights and protections that we have, nothing that guarantees the future rights of EU citizens living here or our ability to attract more of the people we need for the strength of our economy, the delivery of our public services or the diversity of our society.
“There’s a not a single reference to Scotland either in the Withdrawal Agreement or in the absurdly simplistic paper on the future relationship.
“But the chaos of Brexit was inevitable, but we also need to face up to equally inevitable fact that Scotland will only get the strong future relationship that we want with Europe - as the overwhelming majority of people in Scotland voted for - if we get out there, campaign for it and persuade people to vote for Scotland to become a full, independent EU member country.”
Ms Sturgeon told MSPs the case for Scottish independence is growing “stronger every day” and confirmed she will introduce plans for a second referendum.
“I will come back to the chamber and set out my views on that, the precise detail of that, when we have clarity,” she said.
“Obviously we have now seen the terms of the deal. It remains to be seen whether that will go to a vote in the House of Commons in the next couple of weeks. We will see how that saga plays out then I will give that commitment as I said I would.”
She added: “I have no doubt that Scotland will get the opportunity to chose again on the question of independence and when it does I am confident that Scotland will choose to be an independent country.
The First Minister said the past two years have seen the Scottish government “sidelined” on the Brexit negotiations, while the powers of the Scottish Parliament have been undermined.
“The case for independence has grown stronger each and every single day and the sooner this Parliament is independent, the sooner this country is independent and is no longer at the mercy of Tory Governments who do not have our best interests at heart the better,” she added.
“That time will come and when it does I have no doubt that Scotland will choose to be independent.”
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