President Donald Trump said on Saturday that it was "inconceivable" that the "government would break into" the office of his former longtime lawyer Michael Cohen.

He added that it was "totally unheard of & perhaps illegal" for a "lawyer to tape a client."

Trump's comments came after it was reported that Cohen secretly recorded a conversation with Trump in September 2016 about payments to a former Playboy model who alleges an affair with Trump.

When Trump found out about the recording, he reportedly said, "I can't believe Michael would do this to me."

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President Donald Trump reacted on Saturday to news that Michael Cohen, his former longtime lawyer, secretly recorded a conversation with Trump in which they discussed payments to a former Playboy model who says she had an affair with Trump.

The conversation reportedly happened in September 2016, just two months before the November election.

"Inconceivable that the government would break into a lawyer's office (early in the morning) - almost unheard of," Trump tweeted. "Even more inconceivable that a lawyer would tape a client - totally unheard of & perhaps illegal. The good news is that your favorite President did nothing wrong!"

The government did not break into Cohen's office. The FBI obtained a warrant to raid his properties in April as part of a federal criminal investigation into whether Cohen committed wire fraud, bank fraud, and campaign finance violations while working for Trump.

Cohen's attorneys are said to have discovered the recording while going through a trove of seized documents and records as part of a privilege review. They shared the recording with Trump's lawyers as well, The New York Times reported, citing three people briefed on the matter.

Legal experts told Business Insider that they found it bizarre that Cohen felt the need to record a conversation with Trump, and some said they had never heard of an attorney secretly recording a client.

The New York State Bar Association calls such secret recording unethical. New York, where the taping reportedly took place, legally requires only one person's consent for such a recording. So Cohen's actions were not illegal.

Mitchell Epner, an attorney at Rottenberg Lipman Rich who was previously an assistant US attorney for the District of New Jersey, told Business Insider that Cohen could have made the recording either "for his own protection" or to ensure he got repaid for an expenditure he thought could have been agreed to in the conversation.

The woman at the center of this payment is Karen McDougal, whom the National Enquirer paid $150,000 in August 2016 for the rights to her story.

But the outlet never published the piece. That practice is known as "catch and kill," and it effectively silenced McDougal about her allegations of a 2006 affair with Trump. Federal investigators had sought documents related to that payment and similar payments to other women in the raids.

David Pecker, the head of American Media Inc., which publishes the National Enquirer, is a longtime friend of both Trump's and Cohen's. Citing a person familiar with the recording, The Washington Post reported Friday that in it, Cohen and Trump discussed a plan to purchase the rights to McDougal's story from Pecker's company for about $150,000.

Trump's attorney Rudy Giuliani confirmed to The Times that Trump discussed payments to McDougal with Cohen, but he said that ultimately no payment was made.

"Nothing in that conversation suggests that he had any knowledge of it in advance," Giuliani told the newspaper of American Media Inc.'s payment. Giuliani added that Trump told Cohen that if he did pay McDougal, it should be in the form of a check instead of cash so that it could be properly recorded, The Times said.

"In the big scheme of things, it's powerful exculpatory evidence," Giuliani said.

But another source told CNN that the conversation was not as Giuliani described, saying the tape was in no way good for Trump. Citing a source familiar with the tapes, CNN reported that Trump, when informed about the September 2016 tape, said, "I can't believe Michael would do this to me."