Michael Cohen made a surprise visit to a New York court on Thursday, and it's likely sealing his full departure from President Trump's side.

Through tweets and guilty pleas, Trump's former attorney has long signaled he was breaking off his partnership with the president. And on Thursday, Cohen stepped into a New York court to affirm a "tentative deal" to cooperate with Special Counsel Robert Mueller and plead guilty to lying about Trump's contacts with Russia, ABC News reports.

Cohen was once Trump's right-hand man, and often discussed questionable business dealings with the president — discussions that Cohen secretly taped and gave to the FBI. But after implicating Trump while pleading guilty to financial crimes in August, Cohen has given more than 70 hours worth of interviews to Mueller's team in their investigation into the Trump campaign's interactions with Russia, sources tell ABC News.

Cohen also gave closed-door testimony to the Senate Intelligence Committee last year, apparently discussing a real estate project in Moscow, per Law360's Pete Brush. Cohen originally said a deal to build a Trump Tower in Moscow "was stopped in January 2016," says CNN's Jim Acosta. But on Thursday, Cohen pleaded guilty to lying about when and where that project actually took place, and said discussions actually continued beyond January, CNN reports via documents being read in court. It's seemingly a continuation of Cohen's cooperation with the special counsel, seeing as a prosecutor from Mueller's office was present in the courtroom, writes The Associated Press.

Read more about Cohen's cooperation at ABC News. Kathryn Krawczyk