Tony Stewart will become owner and driver for Haas/CNC Racing after being granted a letter of release from Joe Gibbs Racing, according to reports Wednesday.

Stewart will officially announce the move to Haas/CNC Racing on Thursday at Chicagoland Speedway. Haas/CNC Racing will be renamed Stewart Haas Racing in 2009.

Stewart, who spent 10 years with Joe Gibbs Racing, will become the highest-paid driver in NASCAR in his new deal.

"We've had a lot of success with Tony in our 12 years here at Joe Gibbs Racing," J.D. Gibbs, president of JGR, said in a statement. "While this moment is bittersweet, we're parting on good terms and we know that each of us has benefited greatly from the other."

Haas currently owns just two cars: the Nos. 66 and 70 Chevrolets. Stewart will own a 50 percent stake in Haas Racing, but his financial investment was not disclosed.

Ryan Newman remains the lead candidate to drive Stewart Haas' second car, sources told ESPN.com, though no deal had yet been finalized Tuesday night.

During his tenure at JGR, which began in 1999, Stewart has recorded 32 victories, a pair of Sprint Cup championships and more than $68 million in winnings.