Darel, 49, who gained fame in Eric Rohmer's A Tale of Springtime in 1990, told Le Parisien newspaper that Weinstein promised to help make her big in America if she became his "part-time" mistress.
She said she first had to beat off his advances after Weinstein's company Miramax bought the 1993 fashion industry comedy A la mode, in which she appeared.
The following year, pushed by her agent, she agreed to meet Weinstein in a Paris hotel.
"He talked to me about a film he wanted to make about World War II and then he began to tell me that he found me very attractive and wanted to have an affair with me," Darel told the paper.
"I told him I was very much in love with my partner but he said that that didn't worry him and he wanted me to be his mistress for a few days a year. That way we could work together. Basically, he said that if I wanted to make it in America, it would be through him."
Seydoux slams industry silence
Bond star Léa Seydoux earlier wrote her own account of her run-ins with Weinstein and others in an industry that, she said, turned a blind eye to abuse.
"That's the most disgusting thing. Everyone knew what Harvey was up to and no one did anything," Spectre star Seydoux wrote in the Guardian.
She said she quickly figured out Weinstein's motives when they met.
"He had a lecherous look. He was using his power to get sex," she wrote. "He's big and fat, so I had to be forceful to resist him. I left his room, thoroughly disgusted."
Two other French actresses, Judith Godrèche and Emma de Caunes, had earlier said they had also suffered at Weinstein's hands.
De Caunes, who starred in the Oscar-nominated The Diving Bell and the Butterfly and the comedy Mr Bean's Holiday, said she was "petrified" when Weinstein emerged naked from the bathroom at the Ritz hotel in Paris where they were having a meeting.
Fired by own company
Weinstein, 65, was sacked by his own company as the allegations of sexual misconduct turned into an avalanche from some of the biggest female stars in Hollywood including Gwyneth Paltrow, Angelina Jolie and Rosanna Arquette.
Three women, including an Italian film star, claimed on Tuesday that Weinstein raped them.
Weinstein has denied all charges, according to a statement from his spokeswoman Sallie Hofmeister.
On Wednesday she offered "no comment" when asked about reports Weinstein was heading to Europe to enter a rehabilitation facility.
- with AFP