William and brother Harry took to the stage in front of a 63,000-strong crowd at Wembley Stadium at the start of the special event they have organised in memory of their mother, on what would have been her 46th birthday.

Sir Elton John opened the event with a performance of Your Song before introducing the two princes, who entered to a standing ovation.

"This event is about all that our mother loved in life - her music, her dancing, her charities and her family and friends," said William, 25. "We just want you to have an awesome time and enjoy the line-up."

Harry said: "It's great to see so many of you here supporting this very special show."

And the 22-year-old royal couldn't resist cracking a gag.

"When William and I first had the idea we forgot we would end up standing here desperately trying to think of something funny to say. We'll leave that to the funny people - and Ricky Gervais," he quipped.

The princes were watched by Harry's girlfriend Chelsy Davy and William's former girlfriend Kate Middleton, who helped them to organise the event.

The concert marks the 10th anniversary of Diana's death and features a line-up of acts including Lily Allen, Take That, Kanye West and Sir Tom Jones.

The princes introduced one of their mother's favourite bands, Eighties heart-throbs Duran Duran, before taking their seats in the royal box.