It was not immediately clear if, as part of the plea deal with Mueller, Manafort would cooperate and provide any information to the special counsel's probe into Russian interference in the 2016 election. Manafort's decision could be mixed news for Trump, who tapped the consultant to serve as his campaign chairman in June 2016 as he was securing the GOP presidential nomination.
But Friday's announcement was a political blow to the presidency ahead of 6 November mid-term elections that could determine whether or not Republicans maintain control of Congress.
In a court document, Manafort said he was guilty of plotting against the United States and plotting to obstruct justice. Trump has raised the idea of a pardon for Manafort with White House aides and others, a source told NPR.
Trump has derided the investigation as a "witch hunt". Prosecutors dropped five other charges that included lobbying violations and money laundering.
It's unclear how the possible deal might affect Manafort's pursuit of a pardon from President Donald Trump.
A Virginia jury convicted Manafort last month on bank and tax fraud charges. The President had previously praised Manafort for refusing to "break" and... Manafort told the judge he wants to plead guilty.
Manafort is expected to appear in court later Friday morning (local time). And during his Virginia trial in August, Manafort's lawyers spent considerable time painting Gates as a liar, embezzler, philanderer and turncoat who would say anything to get a lighter prison sentence.
He also agreed to forfeit some properties.
The latter charge is just a fancy way of saying he got caught moving money around and doing shady stuff for oligarchs-you know, normal Washington D.C. stuff (the worst thing to ever happen to Manafort was winning an election, if we had President Hillary Clinton right now, Manafort would still be peddling the influence of foreign nations in our nation's capital).
"He knows nothing harmful to the president and the plea is the best evidence of that", Rudy Giuliani, the former New York City mayor who is representing Trump in the Russian Federation probe, told Reuters.
Richard Pinedo, who was not involved with the Trump campaign, pleaded guilty in a case related to the Mueller probe in February to aiding and abetting interstate and foreign identity fraud by creating, buying and stealing hundreds of bank account numbers that he sold to individuals to use with large digital payment companies.
After all, while Mueller has played the jail card, Manafort is still likely to be holding the Trump Card - - and no one remains in prison when that card is played. The president has not said whether he would do so.
Prosecutors say that Manafort directed a large scale lobbying operation in the United States for Ukrainian interests without registering with the Justice Department as required by the federal Foreign Agents Registration Act, or FARA.
"Mr. Manafort engaged in a variety of criminal schemes. He did so knowingly, intentionally and willfully", Weissmann said. He also made sure to point out that the case was about conduct that goes back many years.