Nicola Sturgeon has accused Theresa May of committing a "democratic outrage" after the prime minister rejected the SNP's demand for another Scottish independence referendum held before the UK leaves the EU.
May told broadcast journalists on Thursday afternoon that now was "not the time" for another independence vote as the UK government has to put "all its energies" into negotiating the Brexit deal.
Sturgeon announced on Monday that she wants another referendum on independence between autumn 2018 and spring 2019, but that requires the agreement of the UK government for a legal vote.
"Now is not the time" for a second referendum on Scottish independence says UK PM Theresa May #IndyRef2… https://t.co/wx4fqUIPrf
Brexit negotiations are due to conclude in the spring of 2019, but the Conservatives have made clear that they will not allow another independence referendum until Scotland has seen how its new relationship with the EU works.
"When the SNP government say it's the time to start talking about a second independence referendum, I say that just at this point all of our energies should be focused on our negotiations with the European Union about our future relationship," said the prime minister.
"To be talking about an independence referendum would ... make it more difficult for us to be able to get the right deal for Scotland and the right deal for the UK."
The prime minister added: "My message is clear – now is not the time."
The UK government's Scotland secretary, David Mundell, added that Sturgeon's proposal for a pre-Brexit referendum "can't be agreed".
Edinburgh Agreement made 2014 #indyref legal, fair & decisive. @NicolaSturgeon's demand for preBexit #indyref2 not fair and can't be agreed
Mundell told BuzzFeed News on Tuesday he didn't agree that another referendum on independence was inevitable, despite Sturgeon's announcement the day before.
Speaking at a press conference later on Thursday afternoon, Scottish Conservative leader Ruth Davidson laid out her reasons for the refusal of consent, saying the SNP lacked public and political support for a vote.
"We reject conclusively the timetable for a referendum set out by the Scottish government," said Davidson. "For a key reason – because it is unfair to Scottish voters.
"We have just come through a referendum campaign when a key complaint among many people was that they did not have the necessary information to help them make an informed decision. If we were to keep to the first minister's timetable, this is exactly what would happen in Scotland too."
The Scottish Conservative leader went on to say that there should only be a referendum after the UK has left the EU, the majority of the public support it, and there is unanimity among Scotland's political parties that it should take place.
Davidson and Mundell refused to be drawn on when they would accept a referendum – with Mundell saying he wouldn't be "bogged down on arbitrary dates" – but were clear that it was a case of "not now" rather than not ever.
Davidson added: "The SNP must earn the right to ask the question again; they cannot simply claim it and, through that claim, pretend it is true."
The prime minister's announcement comes one day before the SNP's spring conference is due to begin in Aberdeen.
Sturgeon responded to May's earlier announcement in a series of tweets saying that she was not proposing an immediate referendum, but that May was risking "blocking Scotland's right to choose".
2/4 a section 30 order must be discussed and agreed now to enable that timescale.
3/3 If the Tories refuse to do so, they would effectively be blocking Scotland's right to choose when the Brexit terms clear...
4/4 this would be undemocratic given @scotgov clear mandate and also proof positive that the Tories fear the verdict of the Scottish people.
In a later statement, Sturgeon condemned May's intervention as "undemocratic and unsustainable" and said that the prime minister risked causing a "democratic outrage" in Scotland.
Sturgeon said: “As I set out earlier this week, we are not proposing a referendum now – we are proposing to give the people of Scotland a choice once Brexit is clear but before it is too late. The PM does not appear to have listened to our proposal.
“We will put our proposition, based firmly on this government’s democratic mandate, to the Scottish parliament next week, and then we will put our formal proposals to the UK government.
“If the prime minister refuses to engage on the terms of a referendum before Brexit takes place then she is effectively trying to block the people of Scotland having a choice over their future. That would be a democratic outrage.
“It is for the Scottish parliament – not Downing Street – to determine the timing of a referendum, and the decision of the Scottish parliament must be respected. It would be outrageous for the Scottish parliament to be frozen out of the process.
The first minister added: “The Scottish government has a cast-iron democratic mandate to offer people a choice and that mandate must be fulfilled.
“Any bid by the UK government to block the people of Scotland from making a choice will be untenable, undemocratic, and totally unsustainable and clearly shows that the UK government recognises it is out of step with the Scottish people.”