The Scottish government is to publish its draft bill on a second independence referendum.
First Minister Nicola Sturgeon announced at the SNP conference last week that a formal consultation on the legislation would begin within days.
She said Scotland should have the ability to reconsider the issue in light of the vote for Brexit.
And she said it could do so before the UK leaves the European Union.
The draft bill will be formally unveiled by Constitution Secretary Derek Mackay later on Thursday, despite the Scottish Parliament being in recess until next week.
Speaking in advance of the bill’s publication, Ms Sturgeon said the SNP had been elected on a manifesto pledge that Holyrood should be able to consider a second referendum if there was a “material change in circumstances” since the first one in 2014.
She said this would include Scotland being taken out of the EU against its will.
Scotland voted by 62% to 38% to remain in the EU in June’s referendum, but the UK as a whole voted to leave – with Ms Sturgeon immediately instructing Scottish government officials to start drawing up plans for a fresh vote on independence.
However, opinion polls have suggested there has not been a major upsurge in support for independence since the Brexit vote, with a narrow majority still in favour of Scotland remaining in the UK.
Some senior SNP members have cautioned Ms Sturgeon against “rushing into” another independence referendum, which would need to be approved by both the Scottish Parliament and the UK government before it could be held.
UK Prime Minister Theresa May has said that all parts of the UK will leave the EU at the same time despite calls from the SNP for a separate arrangement to be agreed for Scotland.
But she has said she is “willing to listen to options” on Scotland’s future relationship with the EU.
Scottish Conservative leader Ruth Davidson has insisted that neither Scotland’s business community or a majority of Scottish voters want another “divisive” vote on independence.
But Ms Sturgeon said the UK was facing the prospect of a “hard Brexit” that she predicted would do additional damage to Scotland’s economy and budget.
The first minister, who is due to meet Mrs May in London on Monday, said efforts to protect Scotland’s place in Europe would intensify over the coming weeks.
She has said she will put forward specific proposals aimed at keeping Scotland in the single market even if the rest of the UK leaves.
And she will push for “substantial additional powers” for Holyrood as part of the UK’s Article 50 negotiations, including over international deals with other nations and immigration.
Ms Sturgeon added: “However, if it becomes clear that it is the best or only way of safeguarding Scotland’s interests – and in line with our manifesto commitment – parliament must be able to consider the option of an independence referendum, to allow the people of Scotland to vote on independence before the UK leaves the EU.
“I am determined to ensure that Scotland has the ability to make that choice if it is necessary to protect our vital interests.
“If there is an independence referendum, it will not be because the result of the 2014 referendum has not been respected – it will be because the promises to Scotland have not been kept.”
She said the consultation would ensure that any future independence “will – like the 2014 referendum – meet the gold standard of democracy and fairness”.
The Scottish government has said it will propose a statement to the Scottish Parliament next week to update MSPs on developments.
‘Politics of division’
Speaking ahead of the draft bill’s publication, Scottish Conservative leader Ruth Davidson said her party would fight proposals for a second referendum “every step of the way”.
She said: “Instead of using Brexit to further her own political ambitions, Nicola Sturgeon should be working closely with the UK government to address the risks and explore the opportunities this decision creates for industries and sectors across Scotland.
“The fact that Nicola Sturgeon is desperately pushing for (a referendum) shows she has given up on being a first minister for all of Scotland in favour of championing her own separatist agenda.”
Labour’s shadow Scottish secretary Dave Anderson MP branded Ms Sturgeon’s move “reckless”, and said there would be “absolutely no support for a second independence referendum from Labour”.
He added: “It confirms that her (Ms Sturgeon’s) priority is the politics of division, rather than focusing on much-needed improvements to Scotland’s schools or hospitals.
“Our country is already divided following the Tories’ Brexit gamble and a second referendum is the very last thing our fragile economy needs.”
Source: BBC News Reference: www.bbc.co.uk/news