Joe Biden fumed at Today co-anchor Savannah Guthrie after she asked him about how a controversy related to his son Hunter Biden has influenced his presidential campaign.

On Monday morning, the show aired an interview between Guthrie, 48, and Biden, 77, where the two discussed President Trump’s impeachment. Guthrie noted that Trump’s Ukraine-related impeachment intensified scrutiny of Hunter Biden's high-paying job on the board of a Ukrainian natural gas firm.

She claimed there was a “certain irony” about the impeachment in the fact that Trump had asked Ukraine for an investigation into the Bidens, but in the impeachment process, Republicans “ensured that everyone knows” about Hunter Biden's role at Burisma while his father was leading diplomatic efforts in the region as vice president.

“That’s a good thing,” Joe Biden replied. “No one’s found anything wrong with his dealings in Ukraine except they say it sets a bad image.”

Joe Biden said he agreed that the optics of his son's role at Burisma were not good and acknowledged that his son made a similar statement. Guthrie followed up by asking Biden if he thought it was wrong for his son to accept the position with Burisma because the company wanted access to the Obama administration.

“That’s not true,” he responded. “You’re saying things you do not know what you’re talking about. No one said that. Who said that?”

Critics say Hunter Biden, 49, had no experience in the energy sector when he accepted the position at Burisma. He also had a well-documented struggle with drug abuse. Several Republicans have suggested that there was no reason for Burisma to hire Hunter Biden if it were not for his familial ties to the vice president, including Florida Rep. Matt Gaetz, who highlighted Hunter Biden’s rocky past during the House impeachment proceedings.

Guthrie said there were plenty of people who felt it was “kind of sleazy” for Hunter Biden to accept the job and wondered why Burisma would hire him. Joe Biden responded, “Because he’s a very bright guy.”

Biden added that his son should “speak for himself” about whether it was right to accept the job, adding, “He’s a grown man.”

This was likely one of the final nationwide interviews from Joe Biden before the Iowa caucuses take place Monday evening. According to a RealClearPolitics average of polls, Biden trails Vermont Sen. Bernie Sanders in Iowa by 4 percentage points.