Biden repeatedly says 'I don't remember' regarding classified documents in newly released Hur interview audio

"I don't remember," Biden replied. "And I'm not supposed to speculate, right?"

"Correct," Biden's attorney, Bob Bauer, chimed in.

"So, OK, well, I don't remember, and it may have been - I just don't remember," the former president mumbled.

Then, leading to the "classified stuff downstairs" comment, Zwonitzer asked Biden if he had found any documents in his home or if he told Zwonitzer about finding any while they worked together on the book in 2017.

Stumbling over his words, Biden replied, "No, the only thing I can remember is I wanted to be clear to him that I didn't want what he just heard me say about the memo to Barack, even though it wasn't a top secret thing (indiscernible), I didn't, I didn't want any of that mentioned. It was confidential."

He clarified he didn't mean confidential in the classification sense, but that he did not want it included in the book about his son, Beau.

They discussed boxes in the library, hallway and the "back of the garage," with Biden noting he did not know "where in the hell" all of it was going, but that was the extent of his knowledge of what they contained.

"Not like I'm looking for something, like I'm trying to compile things. But just what'd they pack up, what's here," Biden said.

After Hur described the former president as "a sympathetic, well-meaning, elderly man with a poor memory," Biden fired back, saying, "I'm well-meaning, and I'm an elderly man, and I know what the hell I'm doing. I've been president. I put this country back on its feet. I don't need his recommendation."

Fox News Digital's Brie Stimson contributed to this report.