NEW YORK (AFP) – Former IMF chief Dominique Strauss-Kahn was spending his first day outside a prison on Saturday after his lawyers posted $6 million bond in the wake of his indictment on sexual assault and attempted rape charges.

Strauss-Kahn was freed from New York's Rikers Island jail on Friday, trading a jumpsuit for civilian clothes and an isolated cell for an apartment with visits from family and friends.

The house arrest of the former IMF chief, who has been accused of sexually assaulting a hotel maid, was approved by a judge.

Strauss-Kahn will live under the constant surveillance by the private security firm Stroz Friedberg at a secure building at the south end of Broadway near Ground Zero.

Judge Michael Obus earlier ordered the 62-year-old veteran French politician to be released to the home detention after plans for him to live in a plush apartment rented by his wife, Anne Sinclair, reportedly fell through when residents in the complex objected.

Obus agreed at a new hearing that Strauss-Kahn could be handed over to the security firm and put up in temporary accommodation until a more permanent apartment is found.

He must wear an electronic monitoring bracelet at all times, be under at least one armed guard, and the apartment must have 24-hour video monitoring and alarms on all exterior doors.

After almost a week in police custody, including four humiliating nights in Rikers, the move will bring Strauss-Kahn great relief as well as many of the trappings, if not the reality, of freedom.

"Mr Strauss-Kahn will be permitted to leave his home and travel within Manhattan solely for the following reasons: scheduled court appearances, meetings with his counsel, medical appointments, and weekly religious observance," the bail agreement said.

An earlier provision that Strauss-Kahn had to give court officials 24 hours' notice each time he wanted to leave his new digs was relaxed in favor of the defense to just six hours.

Camille, Strauss-Kahn's daughter by a previous marriage, lives in Manhattan on the Upper West Side as she completes her graduate studies at Columbia University.

Lawyers for Strauss-Kahn convinced a judge on Thursday to release him on bail pending trial, under strict provisions.

The veteran politician has resigned as head of the International Monetary Fund under the weight of a scandal that has also ended any hope he had of replacing Nicolas Sarkozy as French president in 2012.

The case has sent ripples around the globe, setting off a heated battle between Europe and emerging powers over who should fill his role at the world lender, which is bailing out failing economies left, right and center.

French Finance Minister Christine Lagarde is tipped as a likely successor but developing nations such as Brazil, Mexico and China have urged a rethink of the conventional wisdom that an IMF chief has to come from Europe.

Tharman Shanmugaratnam, chairman of the International Monetary and Financial Committee (IMFC), called Saturday for an "open" and "merit-based" selection process of a new IMF head.

A grand jury voted to indict Strauss-Kahn on all seven charges related to the alleged sexual assault and attempted rape of the maid on Saturday in his luxury suite at Manhattan's Sofitel hotel.

Strauss-Kahn has denied all charges and is expected to enter a plea of not guilty at his next court appearance on June 6. He could spend the rest of his life in prison if found guilty.

US media say police have taken forensic evidence from the hotel, including bodily fluids found on a section of rug where the alleged victim remembered spitting after she says Strauss-Kahn assaulted her and forced her to perform oral sex.

Jeff Shapiro, a lawyer for Strauss-Kahn's accuser, has said his 32-year-old client, who has not been identified except by some in the French media, was "alarmed" at the prospect of her alleged attacker leaving jail.

She testified on Wednesday and Thursday before the grand jury that later decided to send the case to trial.

If Strauss-Kahn was to plead guilty there would be no trial, but this is considered highly unlikely.

His star lawyer, Benjamin Brafman, said earlier this week the evidence "will not be consistent with a forcible encounter," suggesting the defense was preparing to go to trial and could argue that whatever happened was consensual.