Trump was recorded saying he knew he had a classified document.

Mr. Trump went on a tear about General Milley.

“Isn’t it amazing, I have a big pile of papers,” Mr. Trump said at one point. Papers could be heard rustling, and then Mr. Trump began appearing to point to a specific document, saying, “Look, this was him.” At another point he said, “This was the Defense Department and him.”

He described something in front of him as “like, highly confidential,” and maintained it was really General Milley who wanted to attack Iran (in fact, General Milley cautioned against such a move).

At one point Mr. Trump was interrupted, and a woman in the room could be heard on the recording referencing Hillary Clinton, the former secretary of state whose email server Mr. Trump used as an attack line during the 2016 presidential campaign. Mr. Trump said Mrs. Clinton would send material “to Anthony Weiner, that pervert,” referring to the former congressman who was married to an aide to Mrs. Clinton.

Mr. Trump and his allies have repeatedly asserted that, while still in office, he had declassified all the material he took with him from the White House (though the charges may not rely on whether anything was classified). But his assertion appeared to be undercut by the recording.

“As president, I could have declassified them, now I can’t,” Mr. Trump was recorded saying, according to the person familiar with its contents. He then reiterated something was “classified” as he and one of the women in the room talked over each other, according to the person familiar with its contents.

“Isn’t that interesting? It’s so cool,” Mr. Trump said, adding, “You probably almost didn’t believe me, but now you believe me.”