Washington CNN  — 

Former Vice President Joe Biden’s son Hunter Biden said he used “poor judgment” in serving on the board of a Ukrainian gas company because it has become a political liability for his father.

“I did nothing wrong at all,” he said in an interview with ABC News recorded over the weekend at his home in Los Angeles and broadcast Tuesday. “However, was it poor judgment to be in the middle of something that is – it’s a swamp, in many ways? Yeah.”

“Did I do anything improper? No, not in any way. Not in any way whatsoever,” he said.

The interview was the first time Hunter Biden had responded to questions about his foreign business ties, which President Donald Trump, his attorney Rudy Giuliani and his Republican allies used to characterize the former vice president’s family as corrupt. There is no evidence of wrongdoing by either Joe or Hunter Biden.

Trump has pushed an unproven accusation that then-Vice President Biden improperly tried to help his son by pressuring the Ukrainian government to fire the country’s prosecutor general. Hunter Biden served on the board of the Ukrainian natural gas company at the time.

The Obama administration, American allies, the International Monetary Fund and Ukrainian anti-corruption activists, among others, had all made clear that they were displeased with the performance of Viktor Shokin, who became prosecutor general in 2015.

Hunter Biden said he and his father only had one discussion about Ukraine, in which Joe Biden said, “I hope you know what you’re doing,” and Hunter Biden said he responded, “I do.”

“And that was literally the end of the discussion,” Hunter Biden said.

He also acknowledged that he would “probably not” have been asked to serve on the board of the Ukrainian company if his father was not vice president.

Asked if he had regrets, Biden replied, “What I regret is not taking into account that there would be a Rudy Giuliani and a President of the United States that would be listening to this ridiculous conspiracy idea – which has again been completely debunked by everyone.”

“You know what? I’m a human. And you know what, did I make a mistake? Well, maybe in the grand scheme of things, yeah,” he said. “But did I make a mistake based on some unethical lapse? Absolutely not.”

Hunter Biden also responded to attacks from Trump’s sons, Eric and Don Jr., saying the two are “out of a B movie. I mean, they really are.”

“This isn’t real stuff. It isn’t. It truly isn’t. That part of it, that Barnum and Bailey – you know, say anything, do anything you want, I mean, like, you know – Donald Prince Humperdinck Trump Jr. is not something that I really care about,” Biden said, comparing the President’s son to the antagonist from “The Princess Bride.”

In recent days, Hunter Biden has moved to defuse the political damage his foreign business dealings could do to his father’s presidential campaign.

He had already departed the board of the Ukrainian company, and said that he would step down from his role on the board of a private equity fund backed by Chinese government-owned entities. He also said on Sunday he would not work for any foreign-owned company if his father is elected president in 2020.

“Hunter always understood that his father would be guided, entirely and unequivocally, by established U.S. policy, regardless of its effects on Hunter’s professional interests,” according to a statement released by his attorney. “He never anticipated the barrage of false charges against both him and his father by the President of the United States.”

Later Tuesday, Joe Biden will appear on stage for the CNN/New York Times Democratic presidential debate. The former vice president on Sunday told reporters that his family and associates would not work for foreign companies if he is elected president, saying he would have “build on the squeaky clean, transparent environment” that he believes was reminiscent of former President Barack Obama’s administration. He then unveiled a plan Monday to “restore” ethics in government.

The Biden campaign was informed of Hunter Biden’s Sunday statement and new TV interview, but the decisions about when and how to speak have been Hunter Biden’s, not the campaign’s.

Trump faces an impeachment probe in the Democratic-led House over his urging the Ukrainian President in a July phone call to investigate the Bidens. That phone call led to a whistleblower complaint that in part alleges Trump withheld US aid to Ukraine over the matter. Trump has denied doing anything improper.

CNN’s Jeff Zeleny, Arlette Saenz and Caroline Kelly contributed to this report.