In an interview with ITV’s Good Morning Britain, Mr Trump said that he had known nothing about the organisation when he made the social media postings.
“If you are telling me they’re horrible people, horrible, racist people, I would certainly apologise if you’d like me to do that,” he told presenter Piers Morgan.
“I know nothing about them and I know nothing about them today other than I read a little bit,” he added.
The US President’s apparent show of contrition stands in contrast to his reaction when Theresa May criticised his decision to retweet Britain First in November last year.
He told the Prime Minister, via Twitter: “Theresa @theresamay, don’t focus on me, focus on the destructive Radical Islamic Terrorism that is taking place within the United Kingdom. We are doing just fine!”
Mr Trump said he had not known what Britain First was when he made the three re-tweets last November.
He said that he had made the posts because of his opposition to radical Islamic terrorism.
“Perhaps it was a big story in Britain, perhaps it was a big story in the UK, but in the United States it wasn’t a big story.
“They had a couple of depictions of radical Islamic terror. It was done because I am a big believer in fighting radical Islamic terror. This was a depiction of radical Islamic terror.”
Despite his online run-in with the PM last year, Mr Trump said the pair had a “very good relationship” when they met at the Davos economic summit on Thursday.
“She’s been doing a very good job. We actually have a very good relationship, although a lot of people think we don’t.
“I support her, I support a lot of what she does and a lot of what she says and I support you militarily very much. We will come to your defence if anything should happen, which hopefully will never happen. I am a tremendous supporter of the UK”, he added.
Additional reporting by agencies
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