Chris Carmack, better known as Luke Ward in US teen drama The O.C., may not be back for the show's second season.

According to the New York Post, Carmack declined to sign a contract for the new series because producers couldn't guarantee him airtime in the upcoming year.

"It's not about money," Carmack's representative told the newspaper. "They gave him a generous raise. They just refused to give him a guarantee. He's bummed people would think he would leave the show because of money. Chris has a lot going on. He couldn't sign a contract without a guarantee.

"He is doing a movie with Dennis Hopper for USA, 'The Last Ride,' and has some other things on the table. Chris decided to keep on working without a contract and pursue other roles."

Carmack's costars, including Benjamin McKenzie (Ryan), Adam Brody (Seth), Mischa Barton (Marissa) and Peter Gallagher (Sandy), are understood to have signed contracts that give them guaranteed airtime.