Ex-sports minister Richard Caborn admits 'being economical with truth' to get Nelson Mandela to support London 2012 Olympic bid

However, the Queen had not in fact made such a comment to him.

Mr Caborn, who was an MP in his home city of Sheffield at the time of the bidding process as well as being Sports Minister, said: “I knew Mandela as I had been treasurer of the anti-apartheid movement and I had met Mandela on a number of occasions when he was over here.

"I went to see him and we got chatting about many things. The Queen and him got on incredibly well.

“I said: ‘Madiba, we’ve made a bid for the Olympics – is there any chance you could offer some support?’

"I said we are the only Commonwealth country bidding, which was absolutely true, and added the Queen would love you to support it. He said, ‘Richard, if the Queen wants me to support London, I will’ and the rest is history.”

How Richard Caborn got the Games to London – and built legacy in Sheffield

Mr Mandela subsequently provided his public support for the bid, making a statement in April 2005 which said: "There is no city like London. It is a wonderfully diverse and open city providing a home to hundreds of different nationalities from all over the world. I can't think of a better place than London to hold an event that unites the world.

"The Games in London will inspire athletes as well as young people around the world and ensure that the Olympic Games remain the dream for future generations. London would offer something very special to the Olympic Movement, including great new sporting facilities and a legacy for generations to come."

His backing was described at the time as a “huge coup” for the London bid and Mr Caborn held a press conference in Johannesburg to announce it.

He said at the time: "It is an honour to have such a respected international figure supporting our 2012 Olympic and Paralympic bid.

"The recent history of South Africa shows the power of sport to bring communities together. This is our aim for a London Games, to help unite the nations of the world in one of its most diverse cities.

"Nelson Mandela's backing for London 2012 is a powerful indication of the breadth of support that our bid is receiving all over the world - and a recognition of the special qualities and values we think a London Games would bring to the Olympic movement.”

London’s bid subsequently succeeded a few months later.

Mr Caborn says he later confessed what he had done to the Queen.

“I’m a Privy Counsellor and at the end of one meeting, I said, ‘Ma’am, I have been a little economical with the truth’ and I told her the story. I shall never forget her face because she just smiled at me. I thought, ‘Phew, I’m not going to the Tower!’”