Paul Manafort pleaded guilty on Friday to two counts of conspiracy to obstruct justice and conspiracy against the US.
Andrew Weissman, a prosecutor on the special counsel Robert Mueller's team, also told US District Judge Amy Berman Jackson that Manafort's plea deal includes an agreement to cooperate with prosecutors in the special counsel's investigation, which is probing Russia's interference in the 2016 election and whether members of President Donald Trump's campaign colluded with Moscow to tilt the race in his favor.
Manafort is the former chairman of Trump's campaign. He was the subject of two indictments from Mueller's office and was convicted on eight out of 18 counts of tax and bank fraud last month after his first trial in Virginia.
The second indictment, brought in Washington, DC, charged him with conspiracy, obstruction, money laundering, false statements, and illegal lobbying.
During Manafort's plea hearing on Friday, Jackson dismissed the remaining 10 counts from the Virginia indictment.
Confirmation of Manafort's impending guilty plea first emerged Friday morning, when prosecutors filed a criminal information against the former Trump campaign chairman. An information is a type of charging document prosecutors use to detail a defendant's alleged criminal activity after striking a plea deal with them.
Both indictments center around Manafort's political consulting work from 2006 to 2015 for pro-Russian interests like Ukraine's Party of Regions and former Ukrainian President Viktor Yanukovych.
In the Washington, DC, case, prosecutors alleged that Manafort did not register as a foreign agent while lobbying on behalf of Yanukovych and the Party of Regions. They also accused him of making misleading statements about his overseas work, conspiring to launder money, and attempting to tamper with witness testimony.
Rudy Giuliani, President Donald Trump's lead defense attorney,told Politicoearlier this week that the president's legal team was not concerned about the possibility of a plea deal in Manafort's case because they were convinced he wouldn't say anything damaging about Trump.
He did not immediately respond to a request for comment regarding Manafort's cooperation deal.
White House press secretary Sarah Huckabee Sanders said Manafort's case "had absolutely nothing to do with the President or his victorious 2016 Presidential campaign."
"It is totally unrelated," she said.
But Manafort is a significant figure in several threads of the Russia investigation. He led the Trump campaign from March to August of 2016, during one of the most pivotal periods in the election season.
During that time he exchanged emails with a former Russian intelligence operative, Konstantin Kilimnik, offering the Russian oligarch Oleg Deripaska "private briefings" about the campaign in what might have been an attempt to resolve a long-standing financial dispute with Deripaska.
He spearheaded the campaign when WikiLeaks published thousands of emails that Russia had stolen from the Democratic National Committee. He was also one of three top campaign officials who attended a June 2016 meeting at Trump Tower with two Russian lobbyists offering dirt on Hillary Clinton as part of the Russian government's support for Trump's candidacy.
This story is developing. Check back for updates.