A newly unearthed video shows the Queen giggling as she made small talk and chatted in French with world leaders at the G7 summit in 1991.
A clip from the 1992 BBC documentary 'Elizabeth R' showing members of the royal family at a drinks reception at Buckingham Palace has gone viral after it was shared online.
In one fascinating moment, the monarch, then 65, could be seen speaking to Secretary of State James Baker and former Prime Minister Ted Heath, who spoke of visiting Saddam Hussein in Baghdad.
After he told the Queen he had visited the country, she could be seen laughing, before touching his arm and saying: 'I know you did. But you are expendable now.'
Royal commentators were quick to comment on the video, with Valentine Low tweeting: 'What is noticeable here: 1. How well informed and articulate the Queen is and 2. How the men, including Heath, insist on talking over her.'
A newly unearthed video from the 1992 documentary Elizabeth R shows the Queen, then 65, giggling as she made small talk and chatted in French with world leaders at the G7 summit in 1991
Princess Diana could also be seen in the video making small talk with First Lady Barbara Bush, with the two laughing about lining up for a photograph
The gathering included the Duke of Edinburgh, the Prince and Princess of Wales, John Major, George H. W. Bush, François Mitterrand, Helmut Kohl, Margaret Thatcher and Heath.
During a conversation with Heath, the Queen referred to Baker, saying: 'He couldn't go to Baghdad at that moment like you could.'
Heath replied: 'Ma'am I went to Baghdad.'
The Queen laughed and touched Heath's arm as she joked: 'Yes I know you did but you're expendable. He couldn't go to Baghdad at that moment.'
Meanwhile Prince Charles chatted with a fellow attendee about his painting skills and attending a summer school
The Queen also showed off her French skills, introducing a guest to then Prime Minister Heath by saying: 'You know all these people, and you know Mr Heath.'
Later, the royal joined an American attendee and Heath as they spoke about an unnamed man.
Heath told the pair: 'I was absolutely blunt with him and told him the situation...now I get a message back that says he rather wishes he listened to my advice.'
The Queen replied: 'I mean, I wonder, is he master of his own situation? It's very interesting isn't it to have someone morally, nominally, every way else defeated...'
The Queen could be seen laughing with Prime Minister Edward Heath after joking that he was 'expendable' in the clip
Meanwhile in another moment, Princess Diana could be seen laughing with Barbara Bush as they were told to 'line up' for a photo of the occasion.
Diana giggled as Barbara responded that it was 'just the boys', with the late princess adding: 'Boys only!'
Meanwhile Prince Charles could be heard explaining: '[I'm going to] summer school again this year...I'm quite pleased because I managed to fund it with the sale of my own lithographs so at least I feel I have earned it.'
The clip captures rare candid moments for the members of the royal family, who have rarely appeared in such behind-the-scenes documentaries.
It was made by BBC to mark the Queen's Ruby Jubilee and filming took place over the course of 18 months.
It was viewed and approved by the royal family before it aired on BBC in 1992.