Federal prosecutors have obtained a recording of Donald Trump acknowledging he kept a classified Pentagon document about a potential attack on Iran after leaving the White House, according to CNN.

The recording from the summer of 2021 indicates Mr Trump understood he retained classified material after leaving the White House, the cable network said.

The former president’s on-tape remarks suggest he would like to share the information but he is aware of limitations on his ability to declassify records after leaving office.

CNN did not listen to the recording but cited multiple unidentified sources describing it.

Such a recording could potentially heighten Mr Trump’s legal jeopardy in the federal investigation into his handling of dozens of classified documents as he seeks to regain the presidency in 2024.

The Justice Department is investigating whether Mr Trump, 76, broke the law by removing government records, including several marked as top secret, and taking them to his Mar-a-Lago resort in Florida after leaving office.

The recording is of a July 2021 meeting held at Mr Trump’s Bedminster, New Jersey golf club, according to CNN. It involved two people working on an autobiography of Mr Trump’s former chief of staff, Mark Meadows, as well as several Trump aides.

Mr Meadows’ autobiography includes an account of what appears to be the same meeting, during which Mr Trump described a four-page report by America’s top general, Mark Milley.

The autobiography describes a potential plan by Gen Milley to attack Iran, including deploying huge numbers of US troops.

The document Mr Trump references on the recording was not produced by Gen Milley, CNN was told. One source told the network that Mr Trump refers to the document as if it is in front of him.

The recording suggests prosecutors are probing further into Mr Trump’s handling of classified documents than previously known.

The FBI raided Mar-a-Lago last August and recovered at least 300 classified documents, including US secrets that may have come from human spies.

It was later reported that classified details on Iran’s missile programme were among the files discovered by the FBI.

Mr Trump has denied wrongdoing, claiming that he declassified all documents in his possession. Mr Trump said a president can declassify information “even by thinking about it”.

Steven Cheung, a Trump campaign spokesman, declined to comment on reports of a recording, but said “leaks”from the federal investigation were intended to “inflame tensions”.

“Leaks from radical partisans behind this political persecution are designed to inflame tensions and continue the media’s harassment of President Trump and his supporters”.

Peter Carr, the spokesperson for Special Counsel Jack Smith’s office at the Justice Department, declined to comment.

Mr Smith’s probe includes whether Mr Trump or his associates obstructed the Justice Department’s probe into his retention of thousands of government records, about 300 of which were marked classified.

The special counsel is also investigating efforts to overturn Mr Trump’s 2020 election loss that culminated in the deadly January 6, 2021, attack on the US Capitol.

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