Police in New York and London have confirmed they are investigating historic sexual assault allegations against Hollywood film producer Harvey Weinstein.

New York Police Department spokesman Peter Donald said on Thursday that investigators are trying to determine whether there were any additional complaints involving Weinstein, now embroiled in a sex abuse scandal.

That includes reviewing police files to see if any women previously reported being assaulted or harassed by him.

So far, no filed complaints have been found, he said, other than one well-known case that prompted an investigation in 2015, but authorities are encouraging anyone with information on Weinstein to contact the department.

Also on Thursday, British media reported London police are investigating an allegation of sexual assault involving Weinstein. London’s Metropolitan police force said it had received an allegation of sexual assault from the Merseyside force in northwest England.

Merseyside police said the allegation was made on Wednesday and concerns “an alleged sexual assault in the London area in the 1980s”.

About 30 women, including actresses Angelina Jolie, Ashley Judd and Gwyneth Paltrow, told The New York Times and The New Yorker magazine that Weinstein had sexually harassed or sexually assaulted them.

Detectives in the NYPD’s special victims unit were instructed to identify and speak with any potential victims, including the women who spoke about their encounters with Weinstein in a recent New Yorker article, according to a law enforcement official.

In The New Yorker expose, a former actress, Lucia Evans, said Weinstein forced her to perform oral sex in 2004 when she was a college student.

At least one other unnamed woman said she was raped by Weinstein, but the article did not disclose when or where it happened. A third woman, actress Asia Argento, told the magazine that Weinstein forcibly performed oral sex on her in 1997 at a hotel in France.

Weinstein, through a spokeswoman, has denied any non-consensual sexual conduct with any women.

The film mogul reappeared briefly on Wednesday outside a Los Angeles home, telling the paparazzi he’s “not doing OK” but he’s hoping for a “second chance”, according to video posted by celebrity website TMZ.

He also told the photographers he needs to “get help” and “we all make mistakes.”

New York detectives already investigated Weinstein once, in 2015, when an Italian model said the studio executive grabbed her breasts and groped her.

Detectives set up a sting where they recorded a conversation between the woman and Weinstein while he tried to persuade her to come into his hotel room.

In his own words: Listen to the disturbing audio

Manhattan District Attorney Cyrus R. Vance Jr. said there wasn’t enough evidence to prosecute the case. Vance said his office’s “best lawyers” examined the evidence before deciding, less than two weeks after the woman first made her allegations, to drop the investigation.

Police investigated that allegation as a case of forcible touching, a misdemeanour with a two-year time limit for bringing charges. The statute of limitations has since expired.

Fallout from the numerous allegations against Weinstein continued on Thursday, with the leaders of the Cannes film festival expressing dismay at the accusations.

Hachette Book Group, one of the country’s top publishers, also announced it had “terminated” Weinstein Books.

– With AAP