Liam Neeson has denied he is a racist in an interview on US television, saying that he had grown up surrounded by bigotry during the Troubles in Northern Ireland.

Neeson sparked outrage in a newspaper interview in which he said that, as a young man, he had wanted to kill a black person after someone close to him had said she had been raped by a black man.

Appearing on Good Morning America, Neeson explained his comments had originally been part of a discussion about the concept of revenge. “I remembered an incident nearly 40 years ago where a very dear friend of mine was brutally raped … I had never felt this feeling before, which was a primal urge to lash out.”

He added: “I’m not racist. I was brought up in the north of Ireland. The Troubles. The 1960s, 70s and early 80s … There was a war going on in the north of Ireland. I had acquaintances who were involved in the Troubles. The bigotry. One Catholic would be killed; the next day one Protestant would be killed … I grew up surrounded by that, but I was never part of it.”

Neeson was also asked if he would have reacted the same had the attacker not been black. He replied: “Definitely. If she had said an Irish, Scot, or a Brit, or a Lithuanian – I know I would have felt the same way. I was trying to show honour and stand up for my dear friend in this terrible medieval fashion … It shocked me when I came down … Luckily, no violence occurred, thanks be to God.”

Neeson’s comments were about a woman he did not identify but who he said had died five years ago. He said that his behaviour lasted “a week, maybe a week and a half … It was horrible, horrible, when I think back, that I did that.”

“I went up and down areas with a cosh, hoping I’d be approached by somebody – I’m ashamed to say that – and I did it for maybe a week, hoping some ‘black bastard’ would come out of a pub and have a go at me about something, you know? So that I could … kill him.”

Neeson’s original interview drew a stream of criticism. In a statement, Malik Russell, director of communications for the NAACP (National Association for the Advancement of Colored People) said: “It’s unfortunate and sick that Liam Neeson would in response to a tragedy simply seek out any black person to murder … Pain suffered is not an excuse for racism.”

In the Guardian, columnist Gary Younge wrote that Neeson’s actions showed black people are “still fair game”. “When some white people look at us they see anything from a misplaced grievance to a cautionary tale. What they do not see are human beings.”

However Neeson did receive support from former footballer John Barnes, who said: “We are all unconscious racists … I have more respect for him now than if he had come out and said, ‘I view all black people as equal, I just view everybody as equal.’” Barnes also alluded to the ongoing controversy over Winston Churchill’s record on race issues. “How is Churchill a hero when he … believes in gassing the lesser races. But he’s a hero. ... But Liam Neeson - someone who admits that, after a week and a half of thinking what he thought, that he was wrong, which is fine as far as I’m concerned - we’re now pillorying him.”

In his Good Morning America interview, Neeson said he had spoken to a priest – as well as trying power walking. He added: “We all pretend we’re politically correct. Sometimes you scratch the surface and discover this racism and bigotry.”