New York (CNN) -- The arraignment for the head of the International Monetary Fund, accused of chasing a housekeeping employee down the hall of his swanky New York hotel suite and trying to sexually assault her, has been pushed back to Monday, as authorities conduct forensic tests, his lawyer said Sunday night.

Dominique Strauss-Kahn was taken into custody late Saturday afternoon, then charged with attempted rape and unlawful imprisonment. Sunday afternoon. His arraignment was supposed to take place soon thereafter, but attorney William Taylor said around 10:20 p.m. Sunday night that it had been delayed.

The reason, besides the late hour, was because his client had consented to a physical and forensic examination that had been requested by police, Taylor said. Those tests were being conducted Sunday night.

Strauss-Kahn is expected to make his first court appearance to be arraigned on the charges Monday, Taylor said. The IMF chief's other attorney, Benjamin Brafman, vowed to vigorously defend him in court, insisting his client is innocent.

Police have said Strauss-Kahn sexually assaulted the 32-year-old woman Saturday at the Sofitel hotel in Manhattan, then quickly headed off to a New York airport to board a Paris-bound flight.

Will IMF chief sex charges impact EU bailout?

The arrest of the 62-year-old, widely considered a leading potential candidate for the French presidency, has triggered intense political chatter across the Atlantic.

Strauss-Kahn is married to French journalist Anne Sinclair. They live in Washington, where the IMF is based. In 2008, the IMF rebuked him -- and he apologized -- for what an independent inquiry found to be an improper, consensual relationship with a female employee.

IMF bylaws state that its officials "shall be immune from legal process with respect to acts performed by them in their official capacity except when the fund waives this immunity." Strauss-Kahn's attorneys did not answer questions from CNN about whether he may claim that diplomatic immunity covers such an allegation.

Deputy New York Police Commissioner Paul Browne said Strauss-Kahn does not have diplomatic immunity in this case and, to the commissioner's knowledge, has not claimed it. CNN senior legal analyst Jeffrey Toobin said it was unlikely to apply to Strauss-Kahn, regardless, because violent crimes like this one typically aren't covered under diplomatic immunity.

IMF spokesman William Murray said that as far as he knows, Strauss-Kahn was not in New York City for IMF business.

At about 1 p.m. Saturday, Strauss-Kahn was in his hotel room when the housekeeping employee came in to clean it, Browne said.

She thought she was alone in the luxury $3,000-a-night suite, but Strauss-Kahn then emerged from a room naked, Browne said.

Strauss-Kahn ran after her down the hallway of the suite, Browne said. The suite has its own foyer, hallway, living room, bathroom, conference room and bedroom.

The woman said Strauss-Kahn pulled her into a bedroom and started attacking her, police said.

She fought him off, she told investigators, but Strauss-Kahn then dragged her into the bathroom and forced himself on her. Police said Strauss-Kahn tried to remove her underwear, but the woman got away.

The employee ran to the front desk, Browne said. Hotel staff alerted the New York Police Department.

By the time officers arrived, Strauss-Kahn had left, leaving his cell phone behind at the hotel, according to Browne.

"The alleged victim was taken to Roosevelt Hospital (in Manhattan) and was treated for minor injuries," Browne said.

Authorities learned the IMF head was on an outbound flight at JFK airport destined for Paris. New York police asked their counterparts at the Port Authority to hold the plane.

Two plainclothes Port Authority police detectives boarded the aircraft "just before the door closed" on the flight, and found Strauss-Kahn seated in first class, said a law enforcement official who had been briefed on the investigation.

He "offered no resistance" when he was led off the plane, after which he was turned over to New York police, the official said.

He was taken into custody and brought to a Manhattan police station for questioning. Strauss-Kahn was formally arrested at 2:15 a.m. Sunday.

The alleged victim later identified Strauss-Kahn out of a lineup at a New York police station, singling him out as the man who had sexually assaulted her, according to a law enforcement source who has direct knowledge of the investigation.

The hotel is cooperating with authorities, said John Sheehan, the hotel's director of safety and security.

"We're taking this matter extremely serious, as it's developing," Sheehan said.

Jorge Tito, the general manager of the French chain's New York hotel, said the alleged victim had worked at the hotel for three years and hotel management was fully satisfied with her work and behavior.

A former French finance minister, national legislator and economics professor in Paris, Strauss-Kahn became the IMF's 10th managing director in November 2007. He is also chairman of the IMF executive board.

The IMF acknowledged Strauss-Kahn's arrest in a statement on its website Sunday.

"Mr. Strauss-Kahn has retained legal counsel, and the IMF has no comment on the case; all inquiries will be referred to his personal lawyer and to the local authorities," said Caroline Atkinson, IMF's director of external relations. "The IMF remains fully functioning and operational."

The fund had planned to "convene an informal session" Sunday to be "briefed on developments" related to Strauss-Kahn, the IMF said. But on Sunday night, agency spokesman William Murray said via e-mail that this executive board meeting had been "postponed pending further developments in New York."

Deputy head John Lipsky serves as acting managing director, while Strauss-Kahn is not in Washington, the IMF said, making him the agency's de facto leader at least as long as Strauss-Kahn is detained in New York. The IMF is a major player in economic inequalities and crises worldwide.

Strauss-Kahn was scheduled to be the keynote speaker at the Brussels Economic Forum Wednesday. Organizers said Sunday his appearance had not been canceled officially, but that they were no longer expecting him to attend.

While Strauss-Kahn hadn't officially entered the race, recent French opinion polls showed him leading prospective Socialist Party presidential candidates.

The surveys also suggested he posed a stiff challenge to incumbent French President Nicolas Sarkozy in the 2012 election.

"If the accusations are true, Strauss-Kahn will not be able to run for president," said Jacques Attali, a former top aide to Socialist former President Francois Mitterrand. Attali now serves as political analyst.

Strauss-Kahn became embroiled in controversy soon after joining the IMF, amid reports -- which he later acknowledged -- that he'd had an improper relationship with a female employee. The physical relationship was consensual, an independent inquiry found.

The world body's executive board concluded in October 2008 that "there was no harassment, favoritism or any other abuse of authority by the managing director."

"Nevertheless, the executive board noted that the incident was regrettable and reflected a serious error of judgment on the part of the managing director, as he has acknowledged and for which he has apologized," the IMF said in a statement at the time.

Strauss-Kahn also issued a statement following the closing of the investigation, noting that he had "apologized for it to the (board of directors), to the staff of the IMF and to my family," as well as "the staff member."

"I agree with the board that the personal behavior of the managing director sets an important tone for the institution and I am committed, going forward, to uphold the high standards that are expected of this position," he said then in the statement.

CNN's Susan Candiotti, Miguel Susana, Rick Martin and Ross Levitt contributed to this report.