Spears' father has control of the singer's assets until July

Jon Eardley, who filed the appeal at Los Angeles Superior Court, claims the singer was not given the notice needed when the "conservatorship" was granted.

The "five-day notice requirement" had been dispensed without "legitimate grounds", court papers say.

Conservatorships are granted when a person cannot look after their affairs.

Personal crisis

At the beginning of February a California state court granted a temporary conservatorship order to James Spears and lawyer Andrew Wallet.

In previous court filings Mr Eardley has claimed he was employed by Ms Spears in a telephone conversation.

However, a federal judge said he could not work for the singer because at the time Mr Eardley claims he was hired, Ms Spears had no authority to take him on.

Mr Spears and Mr Wallet are the only two people who can employ lawyers for her.

Despite the singer's personal crisis, a third single from her 2007 album, Blackout, is to be released.

She appears in the video for Break The Ice as an animated superhero in a futuristic world.