Robert Downey Jr. has spoken for the first time about the interview walk-out with Channel 4’s Krishnan Guru-Murthy last week, calling the British presenter a “bottom-feeding muckracker”.

The highest paid actor in Hollywood in 2014 was speaking on American radio host Howard Stern’s show on Tuesday, about the incident in which he stormed out of an interview promoting his new movie Avengers: Age of Ultron when the line of questioning became personal halfway through.

Robert DowneyRobert Downey Jr. spoke about THAT interview walk-out

Having been asked about his political views in regard to a New York Times interview in 2008 he had given after leaving prison, Downey Jr. said “Are we promoting a movie?” before answering the question testily. A few minutes later, he promptly got up and left after a subsequent question about his family and his past battles with substance abuse.

More: Was Krishnan Guru-Murthy right to question Downey Jr. about drugs?

He told Stern that he was unrepentant about the incident last week, adding “I just wish I’d left sooner.” He said that just because he was speaking about a film meant that he had to be grilled about his own past.

“There’s an assumption that... because you’ve sat down there [to be interviewed] you’re going to be scrutinized like a kiddie fiddler who’s running for mayor,” he argued.

“What I have to do in the future is... give myself permission to say, ‘That is more than likely a syphilitic parasite, and I need to distance myself from this clown. Otherwise, I’m probably going to put hands on somebody, and then there’s a real story’.”

Guru-Murthy gave his views on the incident to British newspaper The Guardian at the weekend. Speaking about what it was like interviewing movie stars in general: “Maybe, like a bad relationship, this just isn’t working. We want different things out of it. I want something serious and illuminating, they just want publicity.”

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