Jonah Hill admits he was "disgusting" to use a homophobic slur.
The 22 Jump Street actor was caught on camera lashing out at a photographer over the weekend but has now apologised for his actions.
In the footage, published on website TMZ earlier today, the actor ignored photographers as he walked through Los Angeles and initially didn't respond when one paparazzo said: "'I like the shorts though, bro. They are pretty sexy."
Shortly afterwards, he could be heard swearing, using several expletives and a homophobic slur.
The 30-year-old Wolf of Wall Street star appeared on Howard Stern's radio show soon after the footage was made public to explain his actions.
He said: "This is a heartbreaking situation for me ... I'm upset ... From the day I was born, and publicly, I've been a gay rights activist ...
This person had been following me around all day saying hurtful things.
"I played into exactly what he wanted and I said a disgusting word ... It's bulls*** and I shouldn't have said that. I'm happy to take the heat for using this disgusting word."
Hill went on to stress his desire that people don't think he is homophobic after making the remark.
He added: "What I won't allow is for anyone - it would break my heart to think that anyone - especially with all the work that I've done and all the loved ones that I have - that I would be against anyone for their sexuality."
Hill's thus-far stainless Hollywood reputation may have been marred by the footage, but the actor has been a strident supporter of LGBT rights issues in the past.
He publicly addressed his opposition to Russia's anti-gay laws ahead of the Sochi Winter Olympics and bought into the 'Love Conquers Hate' T-shirt wearing trend adopted by the famous to pledge their support for the persecuted gay communities in the country.
Explaining why he chose to take part in the campaign, he told E! News at the Governors Awards: "I have tons of gay friends, gay family members. It's like saying, 'Why do you think people should breathe?'
"I support anybody doing whatever they want to do to be who they are."
It comes just days after footage emerged of Justin Bieber telling a racist joke when he was 17. He apologised, said he had grown into a man since then, and was "very sorry".
- Bang! Showbiz with the Independent