Cowell's relationship on the rocks?

X Factor and American Idol judge Simon Cowell is close to splitting from girlfriend Terri Seymour, the News of the World claims today.

The pair have apparently been arguing constantly, although they are still living together in Beverley Hills.

The problems between Cowell and Seymour stem from Terri's worries that Simon could be cheating on her.

Seymour told a friend, "I've become a jealous wreck. He doesn't tell me where he's going any more and I can't stand it. We're rowing all the time and I keep thinking he's cheating. He's very close to a few women on American Idol and I'm sure he's sleeping with them."

A source told the newspaper, "He's been working really hard recently with American Idol and Terri's been putting a lot of pressure on him. Her jealousy is spiralling out of control and he can't stand it. She has been acting like a spoilt child demanding more attention."