Prosecutors are poised to drop all sex assault charges against former International Monetary Fund chief Dominique Strauss-Kahn due to doubts about his accuser's credibility, US media reported yesterday.

PROSECUTORS are poised to drop all sex assault charges against former International Monetary Fund chief Dominique Strauss-Kahn due to doubts about his accuser's credibility, US media reported yesterday.

The Wall Street Journal cited officials familiar with the case who said prosecutors were on the verge of dismissing the charges altogether as doubts increased about the woman's reliability as a witness.

"It would have to be that I believed every word that came out of her mouth, and that I believe in the criminal aspect of what occurred," said Assistant District Attorney Joan Illuzzi-Orbon on whether to proceed with the case.

The New York Post quoted a top investigator as being more emphatic that a dismissal is likely, saying: "We all know this case is not sustainable."

The source told the daily that dismissal of the charges is "a certainty", and likely will happen at Strauss-Kahn's next scheduled court date on July 18.

"Her credibility is so bad now, we know we can't sustain a case with her," a source said, referring to the Guinea-born hotel maid who accused the Frenchman of trying to rape her when she came to clean his luxury suite on May 14.

The paper cited defence sources as describing a different scenario, whereby Strauss-Kahn engaged in consensual sex with the maid, but then angered her by refusing to pay for it, prompting her accusations.

The sexual assault charges drove Strauss-Kahn to resign as head of the IMF and initially appeared to have dashed the political career of the man once seen as a likely future French president.

Last Friday, Strauss-Kahn was released from house arrest after prosecutors said the maid had lied to a grand jury, raising the possibility that the case could be thrown out because of the lack of credibility of its key witness.

While prosecutors still believe there is evidence of a forcible sexual attack, they admitted in a letter to the defence that the woman lied on her asylum application and tax returns.