Oscar-winning actor Casey Affleck has spoken about the allegations of sexual harassment and misconduct levelled against him for the first time, admitting that he had “behaved in a way that was really unprofessional”.

It’s the first time that Affleck, 42, has addressed the allegations that he harassed women on the set of 2010 film I’m Still Here, a film that he both starred in and directed. While he settled the civil lawsuits, both for breach of contract filed by a cinematographer and a producer, out of court at the time, the accusations resurfaced in 2017 when he was nominated for the Best Actor Oscar for his role in Manchester By The Sea.

While he has commented on the lawsuits, he has not spoken in the 10 months since the Hollywood sexual abuse scandal, which led to the Time’s Up and #MeToo movements.

Casey AffleckCasey Affleck spoke about the historic allegations of sexual harassment against him

“It was an unprofessional environment… the buck had to stop with me being one of the producers and I have to accept responsibility for that,” Affleck told the Associated Press this week. “I contributed to that unprofessional environment and I tolerated that kind of behaviour from other people and I wish that I hadn’t.”

He added: “I behaved in a way and allowed others to behave in a way that was really unprofessional. And I’m sorry.”

As a consequence, the Academy broke with tradition when this year’s Best Actress award was not presented by the winner of the previous year’s Best Actor – instead of Affleck, Jodie Foster and Jennifer Lawrence presenting it.

More: Oscars break with protocol by confirming Casey Affleck will NOT present best actress award

“I think it was the right thing to do just given everything that was going on in our culture at the moment,” Affleck reflected. “And having two incredible women go present the best actress award felt like the right thing.”

“In this business women have been underrepresented and underpaid and objectified and diminished and humiliated and belittled in a bazillion ways and just generally had a mountain of grief thrown at them forever. And no one was really making too much of a fuss about it, myself included, until a few women with the kind of courage and wisdom to stand up and say, ‘You know what? Enough is enough’,” he continued.

“Those are the people who are kind of leading this conversation and should be leading the conversation. And I know just enough to know that in general I need to keep my mouth shut and listen and try to figure out what’s going on and be a supporter and a follower in the little, teeny tiny ways that I can.”

Affleck has lately been working on a new film called The Old Man & The Gun, alongside Robert Redford. About his decision to break his silence now, the actor explained: “If I’m not promoting a movie, I’m not going to do any press, so that’s why you haven’t heard from me.”

More: Constance Wu calls out Oscars for nominating Casey Affleck [archive]