NEW YORK — A judge has agreed to free former International Monetary Fund leader Dominique Strauss-Kahn without bail or home confinement in the sexual assault case against him.

The move today comes after prosecutors said an extensive background investigation of the accuser caused them to reassess the case.

The agreement OK’d by State Supreme Court Justice Michael Obus in Manhattan does not give Strauss-Kahn his passport back, meaning he can’t head to France anytime soon. The criminal case against him stands.

Strauss-Kahn was held without bail for nearly a week after his May arrest. He has since posted a total of $6 million in cash bail and bond and has been confined to a Manhattan town house.

He denies allegations of trying to rape a hotel housekeeper. He left the courtroom smiling, holding hands with his wife.

The Manhattan District Attorney’s Office agreed to the release of Strauss-Kahn after it uncovered serious questions about the credibility of a hotel housekeeper who accused the former International Monetary Fund leader of sexual assault, a person familiar with the investigation said.

Investigators have come to believe that the woman lied about some of her activities in the hours around the alleged attack and about her own background, a law enforcement official told the AP on Thursday. The official is familiar with the case but spoke on condition of anonymity to discuss matters not yet made public in court.

Prosecutors think she lied about details on her application for asylum in the U.S., including saying she had been raped in her native Guinea, the official told the AP.

“She actually recounted the entire story to prosecutors and later said it was false,” the official said.

Prosecutors haven’t necessarily reached a new conclusion about the allegations against Strauss-Kahn and have not decided whether to downgrade the charges, the official said. Investigators had earlier said they found traces of Strauss-Kahn’s semen on the maid’s uniform, indicating an encounter, and they haven’t backed away from that.

But the serious reduction in bail — from a $6 million in cash bail and bond under house arrest in a pricey Tribeca loft, to nothing — signals the case is not as serious as initially thought.

The maid told police that Strauss-Kahn chased her down a hallway in his $3,000-a-night suite in New York’s Sofitel hotel, tried to pull down her pantyhose and forced her to perform oral sex before she broke free.

If the case collapses, it could once again shake up the race for the French presidency. Strauss-Kahn, a prominent Socialist, had been seen as a leading potential challenger to conservative President Nicolas Sarkozy in next year’s elections — until the New York hotel allegations embarrassed Strauss-Kahn’s party and led to his resignation from the IMF.

“Those who know Dominique Strauss-Kahn will not be surprised by this evolution of events,” one of his French lawyers, Leon Lef Forster, told the AP in Paris. “What he was accused of has no relation to his personality. It was something that was not credible.”