FORMER Spice Girl Victoria Beckham has signed up to become a judge on American Idol in a one off appearance, her publicist has confirmed. The 35-year-old singer turned fashion designer is thought to be filming her part this week. There had been reports that Beckham would replace Paula Abdul, who said she was leaving the show earlier this week, on a full time basis. Hosted by Ryan Seacrest, American Idol is the most popular show in the US. Around 26 million viewers tune in to watch each episode. Abdul announced she was quitting the TV singing contest after eight years, on her Twitter page. With sadness in my heart, Ive decided not to return, the 47-year-old said. She did not give any reasons for her decision, which ends weeks of speculation about contract talks and her future on the show Seacrest said on his Twitter page that he was shocked and saddened by the news. On Tuesday, it was announced that songwriter Kara DioGuardi will return to the show as a judge alongside Simon Cowell and Randy Jackson. - BBC