Prime Minister David Cameron will jet into Aberdeen this morning to launch a last ditch bid to save the Union.
He is due to speak to local Conservative activists – and warn that Scotland and the rest of the UK “will go our separate ways forever” if there is a Yes vote.
The trip to the north-east follows a series of polls at the weekend which suggested that the battle for Scotland’s future is too close to call.
One survey of 700 people by ICM even showed that the Yes campaign had an eight point lead, with 54% wanting independence and 46% saying No.
A poll of polls by John Curtice, the Strathclyde University expert, put the two campaigns neck-and-neck, with Yes on 46%, No on 47%, and 7% undecided.
Mr Cameron, who held the first UK Cabinet meeting in Aberdeen in February, is expected to say: “This is a decision that could break up our family of nations and rip Scotland from the rest of the UK.
“And we must be very clear. There’s no going back from this. No re-run. This is a once-and-for-all decision.
“If Scotland votes yes, the UK will split, and we will go our separate ways forever.”
First Minister Alex Salmond said yesterday that it was Scotland’s chance to change course.
“My view is this is a once in a generation, perhaps even a once in a lifetime, opportunity for Scotland,” he said.
The SNP leader added that following a Yes vote there would be “urgent business” to bring the country together.
“Firstly it will be a day of celebration, Scotland will have achieved something astonishing in democratic politics.
“The first and urgent business is to bring Scotland together, because on Friday after a Yes vote there will cease to be a Yes campaign and a No campaign, there will be a Team Scotland.”
Labour’s former Home Secretary Lord Reid said the reported 500,000 undecided voters in Scotland should stay at home on Thursday if they remain unsure.
Speaking in Edinburgh, he said: “If you don’t know, genuinely, don’t vote.
“There are a thousand ways to make a protest vote. Gambling with the future of your country and future generations is not the most sensible one of those to choose.”
The police have reportedly cancelled all leave in advance of the referendum on Thursday, as tensions run high.
The Electoral Management Board for Scotland has issued all polling staff with a 58-page referendum handbook stating “it is possible station staff will encounter difficult situations or be faced with confrontational behaviour”.
Police Scotland Assistant Chief Constable Bernard Higgins said: “Policing arrangements are well in hand and will be appropriate and proportionate.”
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