Britney Spears is also embroiled in a custody fight over her two sons

Papers filed in a Los Angeles court state Howard Grossman had been asked to deliver a car to James Spears, who has temporary control of the star's estate.

But the 26-year-old was seen driving around Los Angeles shortly after being released from a psychiatric ward.

Mr Grossman has refused to confirm or deny whether he has been sacked.

It is also alleged he violated court orders by arranging meetings for Ms Spears and her lawyer against her parents' wishes.

BRITNEY'S UNHAPPY 2008 3 January: Carried away on a stretcher after police were called in a custody dispute 5 January: Barred from seeing children 31 January: Taken to psychiatric ward by ambulance 1 February: Father James given control of her estate 5 February: Restraining order placed on Sam Lutfi 6 February: Released early from hospital (above) 8 February: Father can fire business manager, court says

Mr Spears has legal control of his daughter's affairs until Thursday.

"The temporary co-conservators have lost all confidence in their ability to work with Mr Grossman," Mr Spears wrote in papers submitted to the court.

Restraining order

Court Commissioner Reva Goetz gave Spears' parents the right to fire Mr Grossman after a private hearing last week.

James Spears' lawyer, Jeryll Cohen, said Mr Grossman claimed he delivered the car to the singer because she had requested it.

"He wanted to comply with her request because he wanted to 'build her confidence in him'," Mr Cohen said.

The legal papers also claim Mr Grossman refused to hand over e-mails from Sam Lutfi, Ms Spears' friend and sometime manager.

A restraining order has been put in place to prevent Mr Lutfi from contacting the singer, after her mother Lynne accused him of drugging her daughter and cutting off her phone lines.

Earlier this month her parents released a statement stating they were "concerned" about her health after she was released from hospital against the recommendation of her psychiatrist.