The New York Times reported today,

Paul Manafort, who was forced out as President Trump’s campaign chairman last summer after five months of infighting and criticism about his business dealings with pro-Russian interests, disclosed Tuesday that his consulting firm had received more than $17 million over two years from a Ukrainian political party with links to the Kremlin.

The filing serves as a retroactive admission that Mr. Manafort performed work in the United States on behalf of a foreign power — Ukraine’s Party of Regions — without disclosing it at the time, as required by law. The Party of Regions is the political base of former President Viktor F. Yanukovych, who fled to Russia during a popular uprising in 2014.

The Washington Post also published an excellent article on the story: Former Trump campaign chairman Paul Manafort files as foreign agent for Ukraine work

Trump Campaign Chairman Registers as Foreign Agent, The Associated Press

Paul Manafort on the stage at the Republican National Convention in 2016.  Credit Sam Hodgson for The New York Times