The Princess Royal has been hailed as one of the unsung heroes of London 2012 by Games’ chiefs.

Princess Anne is leading the official British delegation which will collect the Olympic Flame in Greece today.

She is president of the British Olympic Association (BOA) and has been a member of the International Olympic Committee (IOC) since 1988.

Speaking in Greece Seb Coe, chairman of the London Organising Committee of the Olympic and Paralympic Games (LOCOG), said of The Princess Royal: “I could not ask more from any board member that I have at LOCOG.

“Her commitment and passion for this is extraordinary from the very moment that we threw our hat in the ring.

“I sometimes remind my board that when we have a board meeting at midday and she arrives, she has possibly already opened two hospitals and a school by that time of the day. Her effort is extraordinary.

“She understands international sport. Crucially, for those of us who have been competitive, we have an ally around the table because she tends to see the world through the eyes of a competitor. It is almost like having an extra member of our athletes’ committee.

“This is somebody who actually asks pinpoint accurate questions and most of them are about the welfare of the competitor - that is a great asset to have on a board of other assets.”

The Princess Royal is the only member of the Royal Family to compete at an Olympics after she took part in Montreal in 1976 as part of the three-day eventing team.

Olympics minister Hugh Robertson, who is also part of the British delegation, said: “I have a theory that she is one of the great unsung heroes of this whole process. She played a key role in delivering the bid.

“She is also president of the British Olympic Association. She is an Olympian herself and has the best part of 30 years of experience of how the IOC works - that has been of inestimable value.

“And because she is who she is, she never stands up and asks for any praise. She has played a remarkable role in all of this. Do not underestimate it.

“It is completely unheralded and largely completely unthanked.”

During the visit to Greece The Princess Royal and Lord Coe visited the Therapeutic Riding School of Greece, which helps people with disabilities. The pair watched children doing their exercises on horses.

Lord Coe also gave the children some London 2012 gifts.