The former Tory leader’s admission that he sought to involve the monarch in the political process was met with a warning from the Palace yesterday that such revelations would only serve to jeopardise relations between the Queen and her prime ministers.
The Queen intervened just four days before the vote in 2014 as she said Scots should “think carefully about the future” as she spoke with well-wishers outside Crathie Kirk near Balmoral on Royal Deeside. The comment was seized upon by the pro-union campaign.
A Royal source revealed there is an “amount of displeasure” at Buckingham Palace, adding that “it serves no-one’s interests” for conversations between the prime minister and the Queen to be made public.
“It makes it very hard for the relationship to thrive,” the source added.
Scotland rejected independence by a margin of 55 per cent to 45 per cent, but polling had suggested the campaigns were running neck and neck going into the final week.
Mr Cameron told the BBC he had asked whether the Queen could “raise an eyebrow” about the prospect of Scotland voting for independence.
He sought to defend the move yesterday, suggesting that claims by former First Minister Alex Salmond, who headed up the Yes campaign, had backed him into a corner.
“The context of this which doesn’t, I think quite come out of the programme is at the time Alex Salmond was going round saying that Her Majesty would be a proud monarch of an independent Scotland,” he said.
“This concerned me because my side of the argument couldn’t really say anything about that. So I had conversations with private secretaries and the like, but I never asked for anything improper to be said or done.”
But the claims were dismissed by Mr Salmond who accused the former prime minister of “digging himself into a right royal hole”.
He added: “Cameron has let the genie out of the bottle. He has revealed that, in his political desperation, he tried to secure a royal intervention in the final stages of the Scottish referendum. Whether he succeeded or not, he was playing fast and loose with the constitution.”
The issue was raised during First Minister’s Questions at Holyrood yesterday when Greens co-leader Patrick Harvie expressed concerns that the monarch could again “interfere” in a future Scottish referendum.
But the SNP leader said: “Scotland’s future should always be a matter for the Scottish people. We know that support for another independence referendum is rising.
“Scotland does have the right to choose our own future and I think the revelations from David Cameron say more about him than anybody else and really demonstrate the panic that was in the heart of the UK government in the run up to the independence referendum five years ago.”
Mr Cameron told the BBC he had sought support from the Queen during the referendum campaign after a poll predicting a Yes victory “panicked” him. He made contact with Buckingham Palace officials in 2014, suggesting the monarch could “raise an eyebrow” in the close-fought campaign.
The former Tory prime minister has now hinted he may have revealed “too much” about his interactions with the Queen, but stressed he had not asked her to say or do anything improper. He added: “I don’t want to say anything more about this, I’m sure some people would think it may possibly even be that I have already said perhaps a little bit too much.”
He said previous remarks he made at the time that the Queen had been “purring down the line” to him after the No result had been a “terrible mistake” for which he apologised immediately.
The revelation is made in a two-part BBC documentary in which the former prime minister reflects on his time in Downing Street.
Boris Johnson declined to be drawn into the row yesterday.
“Not only do I not comment on conversations that I may have held with Her Majesty, but I don’t comment on conversations she may have held with anybody else,” he said.