An American lobbyist has pleaded guilty to one count of failing to register as a foreign agent.
Sam Patten is accused of working on behalf of a pro-Russia Ukrainian political party. He also has ties to former Trump campaign chairman Paul Manafort. He has agreed to work with prosecutors as part of a plea deal, which could aid special counsel Robert Mueller's investigation.
Court filings also accuse Patten of buying tickets to Donald Trump's inauguration ceremony on behalf of a Ukrainian oligarch for total of $50,000.
Patten faces up to five years in prison and a $250,000 fine.