Disgraced movie mogul Harvey Weinstein pleaded not guilty Monday in New York City to a new indictment that includes revised charges of predatory sexual assault, a development that caused the judge to delay the start of his trial until Jan. 6.

The change to the case was intended to open the door for an actress to testify against Weinstein in a rape and sexual assault trial that had been scheduled to start on Sept. 9.

Weinstein mostly kept quiet during a brief appearance in a Manhattan courtroom Monday, aside from some exchanges with Judge James Burke, who at one point scolded him for pulling out his cellphone during the proceeding.

Annabella Sciorra, shown at the Tony Awards in New York in 2011, alleges she was raped by Weinstein after he barged into her apartment in the 1990s. (Charles Sykes/The Associated Press)

Weinstein previously pleaded not guilty to charges accusing him of raping a woman in 2013 and performing a forcible sex act on a different woman in 2006.

The case remains about those two women, but prosecutors said the new indictment was needed to allow a third woman, Annabella Sciorra, to testify. Sciorra, perhaps best known for her work on The Sopranos, alleges Weinstein raped her inside her Manhattan apartment after she starred in a film for his then movie studio in 1993.

Sciorra's lawyer, Gloria Allred, said her client was willing to tell her story to bring Weinstein to justice. She criticized the defence team for saying they would try to get the testimony barred.

"Why are they so afraid of having additional witnesses testify?" she said.

The Associated Press generally does not name people who say they are victims of sexual assault, but Sciorra went public with her story in a story in The New Yorker in October 2017.

Once among Hollywood's most powerful producers, Weinstein has already pleaded not guilty to five criminal charges in the earlier indictment, including rape and predatory sexual assault. He could face a life sentence if convicted.

The two women in the earlier indictment are among about 70 who have accused Weinstein of sexual misconduct dating back decades. Weinstein has denied the allegations and said any sexual encounters were consensual.

Lawyers for Weinstein have asked that the trial be moved, perhaps to Suffolk County on Long Island or to Albany County upstate, because intense media scrutiny in New York City would make it impossible for him to get a fair trial there, according to a court filing.