CNN obtained audio of former US president Donald Trump discussing sensitive military documents he took with him after leaving the White House.

In the two-minute audio clip, Trump can be heard describing a document compiled by General Mark Milley, chairman of the Joint Chiefs of Staff when Trump was president, on the potential attacks against Iran. The discussion of the file was recorded during a 2021 meeting in Bedminster, New Jersey, with people working on Milley’s memoir.

“He said that I wanted to attack Iran. Isn’t it amazing?” Trump says of Milley in the audio clip as the sound is heard of that appears to be shuffling papers. “I have a big pile of papers. This thing just came up. Look. This was him. They presented me this ― this is off the record, but ― they presented me this. This was him. This was the Defense Department and him.”

“All sorts of stuff, pages long. Let’s see here,” the former president continues. “Isn’t that amazing. This totally wins my case, you know, except that it is like highly confidential, secret, this is secret information.”

Trump went on to say the papers he was showing his guest were classified.

“See, as president I could have declassified it,” Trump said in the clip. “Now I can’t, you know, but this is still a secret.”

Trump also joked with several people in the room after his aides laughed about former Secretary of State Hillary Clinton’s email server, saying she would “print that out all the time”.

“No,” Trump added, “she’d send it to Anthony Weiner, the pervert,” referring to the former Democratic congressman who resigned after it was revealed he sent explicit texts.

The recording is reportedly a key piece of evidence in special counsel Jack Smith’s case into Trump’s handling of classified files after his presidency.

Federal prosecutors indicted Trump on 37 criminal counts this month, accusing the former president of repeatedly risking national security and undermining the government’s efforts to see the return of boxes of documents from his Mar-a-Lago club in Florida. The indictment cites the conversation obtained by CNN.

Trump has rejected the claims and pleaded not guilty to all counts. He has said he had the absolute right to take anything he wanted when he left the White House under the Presidential Records Act and that he had a standing order to declassify anything removed from the Oval Office during his presidency.

Prosecutors, however, appear to have homed in on Trump’s own words during their investigation. The indictment lays out at least two conversations — including the one in the CNN file — in which he acknowledged material in his possession was still classified.

US District Judge Aileen Cannon, who is overseeing the case, set an initial trial date of August 14. The Justice Department has asked for a postponement until December, a timeline that would give Trump’s attorneys time to obtain security clearances necessary to review the hoard of classified files referenced in the indictment.