A hotel chambermaid who claimed that she was sexually assaulted by Dominique Strauss-Kahn has sued him for a "violent and sadistic" attack.

Nafissatou Diallo said her life had been left in shambles by the attack and that she had been degraded, violated and robbed of her dignity as a woman. In the lawsuit she was described as an "innocent hardworking immigrant" and Mr Strauss-Kahn was accused of believing he was above the law.

The former chief of the International Monetary Fund was arrested in May and subsequently resigned his position. But he has always maintained his innocence, despite allegations by a French journalist that he had tried to rape her too.

Ms Diallo's credibility as a witness has also been called into question, after it emerged that she had given investigators false information about her background. But in recent weeks she has given a number of high-profile interviews and called for sympathy from the public.

Mr Strauss-Kahn is due in court on August 23 and cannot leave the country, but the prosecution is expected to drop the criminal case.

The new lawsuit is a civil case and is separate from the first. Her lawyers said they wanted a jury trial in the Bronx, where Ms Diallo lives, and damages for the distress caused.

Mr Strauss-Kahn's legal team vowed to fight the case and said it was without merit. His lawyer, Benjamin Brafman, said the filing of the lawsuit backed up their belief that Ms Diallo's motivation was to make money.