NICOLA Sturgeon has edged closer to declaring a new vote on independence after a string of demands over Scotland's European future sparked a fresh rebuttal from Downing Street.

The First Minister yesterday warned that she believes the UK is heading for a "hard Brexit" with limited access to the single market and significant restrictions on the free movement of people. At the same time, she highlighted the features as among five "vital interests" she is determined to protect in recognition of the strong Remain vote north of the border.

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The SNP leader, in a keynote speech on "Scotland’s future in the EU," went on to say that with the UK facing "uncertainty, upheaval and unpredictability", it "may well be that the option that offers us the greatest certainty, stability and the maximum control over our own destiny is that of independence".

She also laid down a challenge to the UK Government, calling for London to prove that the union works for Scotland, "despite evidence to the contrary". She added: "It is surely time now to find ways to demonstrate that Scotland's voice can be heard, our wishes accommodated and our interests protected within the UK."

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However, Theresa May has made clear that she believes Scotland staying in the EU while remaining in the UK is "impracticable" while Scottish secretary David Mundell has dismissed the notion of a special Brexit deal for Scotland as "fanciful".

Number 10 again suggested that there would be no unique post-Brexit agreement for Scotland yesterday, and with the SNP administration showing no willingness to barter away features of EU membership, it looks increasingly apparent that the two Governments are locked on a collision course.

Asked, given Ms May's insistence that "Brexit means Brexit," if Ms Sturgeon was deluding people by suggesting Scotland could remain in the EU while also remaining in the UK, the Prime Minister’s spokeswoman replied: "The PM has been clear this government will be delivering on the will of the British people to leave the EU and we would like to see everyone working together now across the UK to make a success of that.

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"That’s why we want to see the discussions with the devolved administrations focusing on the decision, implementing the decision and how you make a success of that."

Among the other key Brexit tests, highlighted by Ms Sturgeon, was that Scotland should continue to enjoy not only access to the single market but retain influence over how rules are made. It suggests a Norway-style deal, which sees the country pay for access to the single market and accept free movement of people, would not be enough to satisfy the First Minister even if it was secured UK-wide.

The First Minister said: "I'm a life long nationalist - but I said in the immediate aftermath of the EU referendum that, in seeking to chart a way forward for Scotland, independence was not my starting point. That remains the case. Protecting Scotland's interests is my starting point and I will explore all options to do so.

"But I am equally clear about this - if we find that our interests can't be protected in a UK context, independence must be one of those options and Scotland must have the right to consider it."

Opponents at Holyrood accused Ms Sturgeon of setting unrealistic demands she knows cannot be delivered, in a bid to provide a justification for another vote on independence.

Murdo Fraser, the Scottish Conservative finance spokesman, said: "Nicola Sturgeon talks about five tests... She is setting these up to fail to provide another flimsy excuse for a referendum re-run.

"It’s pretty clear the SNP is going to amble through this process, and reach the conclusion it always wanted. It would be pretty astonishing if a party whose whole existence rests on Scotland breaking away from the UK suddenly decided we’d be better off in Britain after all."