Scotland's First Minister Nicola Sturgeon has told Sky News the Prime Minister's opposition to a second independence referendum is "unsustainable".

Her comments came as Theresa May vowed to fight to strengthen the "precious, precious union" and accused the SNP of being "divisive and obsessive" nationalists.

In an escalation of the war of words, the PM told Tory activists in Cardiff, that the First Minister and her party were in a "muddle" and warned the break up of the UK would be "bad for us all".

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But Ms Sturgeon said: "The Prime Minister's position just now - and it's a position I don't think is sustainable - is that she's not even prepared to have the discussion.


"And that is putting her at odds not just with me or the independence case.

"It's putting her at odds with the democratically expressed will of the Scottish Parliament - and that should not be a comfortable place for her to be. I pretty certain it's not a sustainable place for her to be."

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The Scottish leader also said even if the UK secured a free trade deal with the EU's single market she would still seek a referendum as it would be for "people to choose".

She added: "Even the best free trade deal between the UK and the EU is going to be inferior to the position we're in just now, which is full members of the single market."

Earlier, SNP deputy leader Angus Robertson told supporters at the party's spring conference in Aberdeen that there was no doubt a second referendum would be held, even though this has been ruled out by the PM before a Brexit deal was reached.

Downing Street has rejected the suggestion that the SNP could hold a legal vote without Mrs May's approval.

Speaking to party activists, the Tory leader said: "It is now clear that using Brexit as the pretext to engineer a second independence referendum has been the SNP's sole objective ever since last June.

"But it would be bad for Scotland, bad for the United Kingdom, and bad for us all."

She condemned the "divisive and obsessive nationalisms" of the SNP and Plaid Cymru, and poured scorn on the Scottish nationalists over their approach to EU membership.

Mrs May added: "They are happy to see power rest in Brussels. But if those powers come back to London, they want them given to Edinburgh, so that they can try to give them back to Brussels.

"And now they apparently say that an independent Scotland would no longer seek to become a member of the EU after a vote for separation. It is muddle on muddle."