left her guests in stitches after making a hilarious confession during at Buckingham Palace this week. The Princess Royal joined her brother, King Charles and Queen Camilla, as they hosted up to 8,000 guests , as community stalwarts, charity workers and leading figures enjoyed afternoon tea on the lawns.

Anne mingled with guests and baulked at the idea of running a marathon when she met two charity fun runners. Craig McMurrough, 54, and charity partner Sarah Temple, 49, raise funds for an ovarian charity, running events such as the London Marathon and the Great North Run as "Mr and Mrs Ovary" as they are dressed as giant ovaries.

Mr McMurrough, from Cambridge, began his charity campaign following the death of his sister from the disease and when he told Anne he planned to run in the Sydney marathon later this year, she quipped "really, are you joking?".

When shown pictures of their outfits Anne said laughing: "Do you run around like that? Good of you not to turn up like that." The friends have raised more than £100,000 for the charity Ovacome, which supports women diagnosed with ovarian cancer.

During a typical summer gathering, around 27,000 cups of tea, 20,000 sandwiches and 20,000 slices of cake are consumed by those invited, who can wear their national dress, or lounge suit for men and summer dress for women.

The Duke and Duchess of Edinburgh were also part of the royal party, as were the Duke and Duchess of Gloucester, who all spent time meeting guests.

Aside from Wednesday's event, there will be two more of the King's Garden Parties this year-one at Buckingham Palace on May 20 and a second one at the Palace of Holyroodhouse in Scotland on July 1.

Additionally, there will be two themed Garden Parties, both taking place in May at Buckingham Palace.

The first one - The Education and Skills Garden Party - will take place on Wednesday, May 14 and is supported by the Department for Education.

The second one - The Not Forgotten Association Annual Garden Party - will take place on Friday, May 16, and will be hosted by the Duchess of Gloucester, who is patron of the charity.