The bid by Scotland’s First Minister Nicola Sturgeon to stage a second referendum on Scottish independence was formally backed by the Scottish Parliament on Tuesday.
MSPs voted 69 to 59 in favour of seeking permission for a referendum before the UK leaves the EU.
However, the UK government responded quickly by saying it would not enter into negotiations on the proposal to hold a new independence referendum in late 2018 or early 2019.
“It would be unfair to the people of Scotland to ask them to make a crucial decision without the necessary information about our future relationship with Europe, or what an independent Scotland would look like,” the UK government said.
The Scottish government said the Scottish Parliament’s vote gave it a mandate to open formal talks with the UK government on the details of a Section 30 order to enable an independence referendum to take place “when the choice between an independent Scotland and the UK’s Brexit deal is clear.”
Sturgeon said: “It is now the will of Scotland’s democratically elected national parliament that discussions should begin with the UK Government to enable an independence referendum to be held.
“People should be given that choice once the details of the UK’s Brexit deal are clear – and the Prime Minister yesterday confirmed to me that she agrees this will be in 18 months to two years from now.
“Today’s vote must now be respected. The mandate for a referendum is beyond question, and it would be democratically indefensible – and utterly unsustainable – to attempt to stand in the way of it.
“We will now act on the mandate given to us by parliament by making a formal approach to the UK Government within the next few days, after Article 50 has been triggered.
“This is, first and foremost, about giving the people of Scotland a choice on this country’s future.
“We know that Brexit threatens a hugely damaging and uncertain future for Scotland, and it would not be right if the people of Scotland – having been told in 2014 that the only way to protect our place in Europe was to vote against independence – were denied a choice.
“Every other nation in the EU will soon have a say on the terms of Brexit, and on how it impacts Scotland. The people of this nation cannot and must not be the only ones denied a say.
“The Prime Minister says that now is not the time for a referendum.
“I agree with that, which is why I have indicated a timescale no earlier than 18 months from now, when the terms of Brexit are clear – something the PM has now indicated she agrees with.
“It is up to the UK Government to now make clear when they consider a referendum would be appropriate.
“There is clear precedent for how the terms of a referendum made in Scotland can be agreed, and that precedent should be followed.
“The people of Scotland are sovereign, and they will be given a choice on their own future.”
David Mundell, the UK government’s Secretary of State for Scotland, tweeted that a second referendum vote before the Brexit process was complete would be “unfair, so can’t be agreed.”
He added: “Nor will there be any negotiations in response to such a request.”