"Charges have been authorised against Harvey Weinstein, 70, following a review of the evidence gathered by the Metropolitan Police in its investigation," said Rosemary Ainslie, head of the Crown Prosecution Service's (CPS) Special Crime Division.
The CPS said the alleged assault took place in August 1996 in London.
London's Metropolitan Police said the accusation involved a woman, now aged in her 50s.
"It is strange and even unhelpful for them to release this information without having interviewed him, given him any previous disclosure regarding the allegations and not producing an actual charge sheet, nor any plan of how they intend to proceed with the matter," a spokesman for Weinstein told Reuters by email.
"At this point we have the same information as the media."
Weinstein is currently serving a 23-year prison sentence in the United States after being convicted in 2020 of assaulting former production assistant Mimi Haleyi and raping former aspiring actor Jessica Mann.
That conviction was upheld by a New York appeals court last week.
The verdict was considered a landmark in the #MeToo movement where women came forward to accuse dozens of powerful men of sexual misconduct.
Many view the accusations against Weinstein, which surfaced in 2017, as the key spark for that movement.
"The Crown Prosecution Service reminds all concerned that criminal proceedings against the defendant are active and that he has the right to a fair trial," Ainslie said.