An international line-up of pop stars has paid tribute to Princess Diana at a memorial concert watched by her sons princes William and Harry and a crowd of 60,000 at London's Wembley Stadium. Elton John, friend of the princess who sang at her funeral, opened with Your Song in front of giant photographs of Diana taken by Mario Testino that were beamed on to the stage backdrop, and closed proceedings more than six hours later He was followed by veterans Duran Duran, Status Quo, Bryan Ferry, younger acts The Feeling, Fergie from the Black Eyed Peas, Orson, Lily Allen and US rapper Pharrell Williams as well as The English National Ballet, a favourite of Diana's. Welsh crooner Tom Jones also showed he could still rock at 67, getting the crowd, and the princes, to their feet with Kiss. The concert was staged on what would have been Diana's 46th birthday. She died in a car crash in Paris in August 1997, provoking an unprecedented outpouring of grief from the British public for their "queen of hearts". The princes, who danced and joined a Mexican wave during the six-hour music marathon, organised the event to mark the 10th anniversary of their mother's death and celebrate her charity work, which they felt had been forgotten amid negative press. "This evening is about all that our mother loved in life - her music, her dance, her charities and her family and friends," William, 25, said after receiving a standing ovation.