Source: Shell/Pennzoil leaving Harvick

CHARLOTTE, N.C. -- Shell/Pennzoil is leaving Richard Childress Racing's Kevin Harvick after this season to be the primary sponsor for Kurt Busch at Penske Racing, a source close to the situation confirmed Tuesday night.

Miller Lite, which sponsors Busch's car, will move to the No. 12 Penske car driven by Brad Keselowski. Keselowski's car is sponsored by Verizon, but because of NASCAR's exclusive sponsorship with Sprint, the company is not allowed to put its brand identity on the car.

That leaves Harvick, in the last year of his contract with RCR, without a sponsor.

Shell/Pennzoil and Penske Racing will announce their deal, first reported by SceneDaily.com, on Wednesday morning. Shell/Pennzoil has been with Harvick since 2007. Miller Lite has been with Busch, the 2004 Sprint Cup champion, since 2006.

Busch is in the last year of his contract with Penske, but said earlier this year he hoped to stay with the organization. The deal with Shell/Pennzoil is the first step forward finalzing a new deal.

The addition of Shell/Pennzoil means Mobile 1, a competing oil company that sponsors Penske's Sam Hornish Jr., likely will go away.

A source told ESPN.com that Harvick, who reportedly wanted out of his deal with RCR last season, is negotiating with RCR to find a new sponsor and stay with the company he has been with since he replaced the late Dale Earnhardt in 2001.

A source said discussions between RCR and Budweiser, in its last season with Richard Petty Motorsports' Kasey Kahne, have taken place. Kahne signed a deal with Hendrick Motorsports last week to replace Mark Martin in 2012 and drive a car to be determined by team owner Rick Hendrick in 2011.

David Newton covers NASCAR for ESPN.com. He can be reached at dnewtonespn@aol.com.