Prince William and Harry's former royal butler has shared a fond memory of a “crazy” Christmas party he enjoyed with the royal siblings.

Grant Harrold, also known as The Royal Butler, worked for the King and Queen Camilla, as well as Prince William, Princess Kate and Prince Harry up until 2011.

Speaking exclusively to The Independent, Mr Harrold recalled how William and Harry started a “fun” balloon fight during a sit-down Christmas lunch.

He said: "William started blowing up balloons and sending them over to me. You know where you blow it up and let the air out, and I was doing this back to him, thinking 'am I supposed to do this?'.

“I was so confused about the situation. He was doing it to his father and then Harry started doing it and they started putting water in to the balloons. It was crazy, but fun."