Scottish First Minister Nicola Sturgeon faces a make-or-break vote in the Scottish Parliament later, as MSPs decide whether or not to back her fight for a second independence referendum.
She will call on MSPs to back her request to Westminster for a Section 30 order, allowing for a legally-binding vote to be held.
Last week, Ms Sturgeon announced plans to hold another vote on Scotland's future some time between autumn 2018 and spring 2019, but the British Prime Minister Theresa May said "now is not the time" for another referendum.
Conservative, Labour and Liberal Democrat MSPs have said they will block such a ballot.
However, the pro-independence Scottish Greens, who have six MSPs, are expected to give the First Minister the support she needs for her motion to be passed after the conclusion of a two-day debate this afternoon.
Making her case for a new vote on Wednesday, Ms Sturgeon told the Scottish Parliament there was an "unquestionable democratic mandate for an independence referendum".
She said the UK government would be "wrong and unfair" to stand in the way of Scotland "even having a choice", adding that Mrs May should set out a timetable for a referendum if she does not agree with holding it before spring 2019.
Ms Sturgeon added: "The voice of this parliament has been ignored at every step of the way and far from any indication of new powers, we now face the prospect of the UK Government using Brexit to reserve for itself powers in areas that are currently devolved to this parliament."
During a strongly-worded debate, Scottish Conservative leader Ruth Davidson said there was no support in Scotland for a second referendum and accused the SNP of trying
She said: "The people of Scotland don't want this and it won't wash to have a First Minister standing there, washing her hands, saying 'It's not me that's dragging us there, it's with a heavy heart, a big Tory did this and ran away'.
"It won't do, First Minister, take responsibility."
Scottish Labour leader Kezia Dugdale said that for Ms Sturgeon "leaving the UK is the only thing that matters".
She added: "It isn't improving education in Scotland. It isn't lifting children out of poverty. It's independence. That will always come first and it always has."
