Federal prosecutors in Manhattan who are investigating President Trump’s longtime personal lawyer, Michael D. Cohen, have received 12 audio “items” that had been seized by the F.B.I. but had been withheld from investigators, according to a court filing on Monday.

The materials, presumably audio recordings, were turned over to prosecutors on Friday after “the parties” withdrew claims that the items were subject to attorney-client privilege, the filing said.

The authorities have been investigating Mr. Cohen’s role in making hush-money payments to women in advance of the 2016 election, and whether any such action violated federal campaign finance laws.

Also on Friday, The New York Times reported that two months before the election Mr. Cohen had secretly recorded a conversation with Mr. Trump, in which they discussed payments to a former Playboy model, Karen McDougal, who had claimed she had an affair with Mr. Trump.