Simon Cowell, the star of the Fox network's biggest show, American Idol, announced Monday that he will leave the show after this season and will start a new singing competition show, "The X Factor", on Fox starting in 2011.
Fox said Mr. Cowell would be both an executive producer and a judge on "The X Factor", which will have its premiere in the fall of 2011.
At a press event in Pasadena, California, Mr. Cowell said that he did not know who would replace him on Idol, though he joked that the show's host, Ryan Seacrest, could judge the contestants as well as be the host of the show.
For much of the past year Mr. Cowell has said that he was considering leaving Idol. He said that people thought he might be simply negotiating but he said Monday that he was serious all along. "I was offered a lot of money"to stay on, he said, but decided it was time to move on.
"I never wanted to walk out when show was 21 in the ratings," Mr. Cowell said. "You want to go out on a high."
Read more: Simon Cowell to Leave American Idol