IT was quite the crowd that gathered in the Throne Room at St James’s Palace on Saturday to proclaim the new sovereign.

Alex Salmond, Peter Mandelson, Angela Rayner, Menzies Campbell, John McFall … the 200 Privy Counsellors, only a fraction of the membership due to constraints on space, made up a who’s who of politics. Or, at least, a who was who.

Standing at the front were six members of that most exclusive of societies, The Ex-Prime Ministers’ Club.

Tony Blair, Gordon Brown, David Cameron, Theresa May, John Major, and the newest member of the club, Boris Johnson. As members, all had enjoyed a weekly audience with the Queen.

“It’s the club that no-one wants to join and you never get to leave,”said Mr Cameron yesterday.

The six were huddled in discussion with each other, but all that could be heard was a gentle murmur of conversation.

What were they saying, one wondered? Indeed, what had it been like to have an audience with the Queen? What were the insights they most valued? The times they were most grateful for her advice?

As luck and good planning had it, the host of Sundays with Laura Kuenssberg had been wondering the same. To find out more, she interviewed three of the “club” – David Cameron, Theresa May, and Gordon Brown – after the accession ceremony.

“There’s always a good camaraderie amongst us,” said Mr Cameron. “It’s interesting because often they were your principal political opponent and now, when we meet at these things, it’s much more talk about how the children or grandchildren are rather than anything more profound.”

Kuenssberg’s programme was in marked contrast to last week’s chaotic debut. While suitably sombre, and largely taken up with the May/Cameron and Brown interviews, the show included mention of other matters, including the energy price cap and Ukraine. It was a sign of politics, and programming, returning to normal.

All three former Prime Ministers made a point of stressing to Kuenssberg that the weekly audiences with the monarch were strictly private. They spoke in general terms of the Queen’s vast experience and political knowledge, and of lighter moments, such as barbeques at Balmoral (all three), or getting lost on the hills and being rescued by the Queen in her Land Rover (David and Samantha Cameron).

The trio were models of discretion – mostly. At one point, David Cameron managed to add some detail to one of the most intriguing episodes in Scottish political history: what the Queen said, or did not say, on the eve of the 2014 Scottish independence referendum.

The incident took place outside Crathie Kirk when the Queen, pausing to speak to someone in the crowd, was overheard saying, “Well, I hope people will think very carefully about the future.” This was interpreted as a steer against voting for independence.

The day after the vote it was Mr Cameron’s turn to be caught on a stray microphone, boasting that the Queen had “purred” down the telephone when he informed her that independence had been rejected.

Kuenssberg reminded a blushing Mr Cameron of this, asking what it was like to have to apologise to the Queen.

“It was a very upfront and fulsome apology done very quickly at the beginning of an audience,” he replied. “I think that is all I should say. From ever onwards I have been more careful when cameras and microphones are around and I have learned my lesson.”

Asked if the Queen had told him off, Mr Cameron said: “Obviously everything said at those meetings is entirely private.”

What the Queen said or did not say outside Crathie Kirk also came up in yesterday’s Sunday Times. According to Tim Shipman, the paper’s chief political commentator, the incident had been planned.

“This was no accident,” wrote Shipman. “One of her aides had called journalists, including me, in advance to ensure a reporter would be there to record the comments, and then afterwards to make sure they were clear this was a hint she opposed the separation of her kingdoms.”

Mr Cameron also revealed that he had audiences with Prince Charles when the Queen was still on the throne.

“He [the Prince] wanted to start thinking about how to conduct those audiences. From what I saw he will be brilliant at that job, at listening, asking questions, giving wise advice and sage counsel.”

With those parting compliments, the book was closed once more on audiences with the monarch.