The Prime Minister will call on the people of England, Wales and Northern Ireland to send a message to Scotland that “we want you to stay”. In a marked departure from the more negative tone that has typified the pro-Union campaign, Mr Cameron will make the case for Scotland remaining part of the UK.
“We come as a brand – a powerful brand,” he will say. “If we lost Scotland, if the UK changed, we would rip the rug from under our own reputation.
“The plain fact is we matter more in the world together.” In an impassioned speech at the Olympic Park in Stratford, East London, the Prime Minister will wrap himself in the colours of the Union flag, appealing to the “red, white and blue” of the UK.
Citing the patriotism which “came out of the shadows and into the sun” during the 2012 London Olympics when everyone cheered “as one” for Team GB, Mr Cameron will say: “It’s Team GB I want to talk about today. Our United Kingdom.”
He will add: “This is a decision that is squarely and solely for those in Scotland to make.
“But my argument is that though only four million people can vote in this referendum, all 63 million of us are profoundly affected [by the vote on 18 September]”.
And those 63 million could “wake up on 19 September in a different country with a different future ahead of it”, he will say.
Mr Cameron will say that the referendum result is “still up in the air” with just seven months to go. “There can be no complacency about the result of this referendum,” he will say.
“So to everyone in England, Wales and Northern Ireland, everyone, like me, who cares about the United Kingdom, I want to say this: you don’t have a vote but you do have a voice.
“Those voting are our friends, neighbours and family. You do have an influence. Let the message ring out from Manchester to Motherwell, from Pembrokeshire to Perth, from Belfast to Bute, from us to the people of Scotland – let the message be this: We want you to stay.”
Mr Cameron’s appeal has echoes of the final days of the Quebec referendum in 1995 when, faced with the prospect of defeat, those campaigning to keep Canada together called on the rest of the country to express their love for the region with a rally in Montreal attended by 100,000 people from across the country.
The influx of Canadians calling for Quebec to stay is credited with securing a last minute knife-edge victory for those opposed to a breakaway.
“We would be deeply diminished without Scotland,” Mr Cameron will say. “This matters to all our futures. And everyone in the UK can have a voice in this debate.”
He will say that the UK sometimes forgets “how big our reputation is. That the world over, the letters ‘UK’ stand for unique, brilliant, creative, eccentric, ingenious”.
Mr Cameron will argue that it is in Scotland’s interest to remain part of the UK.
“That way, Scotland has the space to take decisions, while still having the security that comes with being part of something bigger.”
But responding to a preview of Mr Cameron’s speech, SNP Deputy First Minister Nicola Sturgeon described his words as “shameful” and “cowardly” and attacked him for “politicising the Olympics”.
“This is a cowardly speech from a Prime Minister who uses the Olympic Park in London to give high-handed lectures against Scotland’s independence, but hasn’t got the guts to come to Scotland or anywhere else to make his case in a head-to-head debate,” Ms Sturgeon said.
“David Cameron, as the Tory Prime Minister, is the very embodiment of the democratic case for a Yes vote for an independent Scotland – and he knows it. A Yes vote will put Scotland’s future in Scotland’s hands, and will mean we will never again have to endure Tory governments, prime ministers and policies we didn’t vote for.”
Ms Sturgeon insisted that using the Olympic spirit “betrays the extent of the jitters now running through the No campaign”. She went on: “They see the polls closing and they are clearly rattled – but to politicise any sporting occasion is shameful.”