President Trump’s former personal lawyer Michael Cohen is willing to testify to Special Council Robert Mueller that Trump was aware of an infamous June 2016 meeting with Russian operatives at Trump Tower before it happened, a source close to Cohen told The Post on Thursday.

The source said that Cohen claims Trump knew and approved of the meeting where Russians offered “dirt” on then-candidate Hillary Clinton — despite Trump’s repeated denials that he was aware it took place.

Cohen was present when Trump was informed by his son, Donald Trump Jr., that the offer had been made, the source said.

President Trump claimed he “didn’t know anything about the meeting” because “nobody told me” about it.

During the meeting, Trump Jr. was joined by Jared Kushner and former Trump campaign chairman Paul Manafort.

The four Russians in the room included a lawyer with Kremlin ties, a businessman who worked for an oligarch and a lobbyist.

The Trump Tower meeting was seen as evidence of the Trump campaign working along with Russians to defeat Hillary Clinton.

President Trump’s lawyer Rudy Giuliani told CNN that Cohen was not credible.

“I expected something like this from Cohen,” Giuliani said. “He’s been lying all week. He’s been lying for years.”