Britney Spears is being sued for $10 million.

The 'Toxic' hitmaker and her father Jamie Spears - who is co-conservator of the star's estate - is the subject of legal action by licensing firm Brand Sense Partners, who allege breach of contract and are claiming they have stopped receiving the 35 per cent commission that was agreed as part of their deal to launch Britney's fragrance line.

The company have filed a request with Los Angeles Superior Court asking for the singer to be ordered to appear for a deposition in relation to the suit, as they say repeated attempts have been blocked because of her conservatorship.

According to documents obtained by RadarOnline.com, Britney was given notice to appear for a deposition on April 29 but couldn't make it, which sparked lawyers on both sides exchanging "over a dozen emails and phone calls counsel in an attempt to cooperate and find a mutually agreeable date for the deposition."

Though Britney's lawyers state the star cannot appear in a deposition because someone else has control of her affairs, Brand Sense insist they want her to do so as she signed the original paperwork.

Their documents state: "Ms. Spears is competent to testify, and she is the key witness in this case. She has direct knowledge of the operative agreement at the heart of this dispute and has signed each of them."

The company argue that the ongoing attempts for a deposition are causing their legal bills to increase and are seeking "sanctions in the amount of $4,500 which represents their reasonable attorney's fees."

A hearing is set for July 11, when a judge will decide if Britney has to appear for the deposition.