Phil Spector’s lead lawyer has resigned from the music producer's murder trial, citing a "difference of opinion on strategy".

Bruce Cutler agreed to stand down after missing several weeks of testimony while filming reality TV show Jury Duty, in which he plays a judge.

"I said that he shouldn't do the closing argument," Spector said outside the courtroom. "With his television show, he wasn't here as much as he should have been."

The 67-year-old is charged with killing B-movie actress Lana Clarkson at his Alhambra, California mansion in February 2003. He denies murder, insisting that she committed suicide.

Cutler told Los Angeles Superior Court Judge Larry Paul Fidler: "There's nothing I can do for Mr Spector. I can no longer effectively represent him."

Closing arguments in the case, which began in April, are scheduled to get underway on September 5, with defence attorney Roger Rosen taking over as Spector's lead lawyer.

The 'Wall of Sound' creator faces 15 years to life in jail if convicted of second degree murder.