(CNN) Federal prosecutors investigating President Donald Trump's former personal attorney Michael Cohen have received 12 audio recordings from the materials seized by the FBI during the searches of Cohen's home, office and hotel room, according to court filings.

The former judge reviewing the material for attorney-client privilege wrote in a court filing Monday that the parties involved in the case had withdrawn their privilege designation on the 12 audio files on Friday. The items had been under consideration by the special master, Barbara Jones, according to the filing.

"Based upon those de-designations, the special master released the 12 items to the government that day," the filing said.

On Friday, Trump attorney Rudy Giuliani said Cohen had secretly recorded a conversation between himself and Trump in which the two discussed a payment to a former Playboy model who has alleged an affair with Trump. That recording, concerning Karen McDougal, is among the 12 files referenced in the court filing, according to a source familiar with the matter, and is the only one of the 12 that is of Cohen and Trump.

Trump's attorneys had waived attorney-client privilege on his behalf on that recording, CNN reported on Friday.

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