Posh and Becks to star in Extras

David and Victoria Beckham will be the star cameos in the final episode of Ricky Gervais's comedy Extras, according to newspaper reports.

The couple, who are big fans of the show, have been lined up to spoof themselves in the last ever Extras, which will be screened on BBC1 at Christmas.

The stars agreed to take part after a personal call from Ricky Gervais, and on learning that a galaxy of other celebs have already signed up, including George Michael, British film actor Clive Owen and Madonna - who will have a run-on role as a jogger who bumps into Ricky's character, Andy Millman, in the park.

"Ricky is over the moon after getting confirmation from David and Victoria," one of his friends told the Sunday Mirror. "He's still discussing how the Beckhams will appear, but they have indicated there is no limit to how silly they are prepared to look."

Previous guest stars on the series have included Robert de Niro, Orlando Bloom, David Bowie, Daniel Radcliffe and Coldplay's Chris Martin.