Mario Vazquez is still tied to American Idol even though he quit the show, producers have revealed.

The singer had cited "personal reasons" for his decision but many had speculated that he had spurned the show's binding contract to pursue a more lucrative solo deal.

"He is not free to sign [with anyone]; he signed that contract two weeks ago," said co-executive producer Nigel Lythgoe, adding that all 24 semi-finalists were required to do the same.

Co-ep Ken Warwick added: "You are going to hear a whole host of 'This is what really happened' on the Internet and wherever else, and all I have to say is don't believe everything you read or see."

Rumours have been buzzing over the exact nature of Vazquez's departure and his "personal reasons." "We know what the personal reasons are and we've made him a promise not to reveal what they are," admitted Lythgoe. "Don't forget this isn't the first time someone has left the show. Marlea Stroman this year actually got through and decided the pressure was too strong, and she missed her son. It does happen. You're taking ordinary people and putting them under an enormous strain and the strain of the media."

American Idol airs this Friday, 8.30pm on ITV2.