Former Trump campaign chairman Paul Manafort’s plea agreement with federal prosecutors apparently fell apart because he allegedly lied to investigators about “personal business dealings” and his contacts with Russian national Konstantin Kilimnik—a former associate who is widely believed to be linked to Russian intelligence. Citing sources familiar with the matter, The Wall Street Journal reports Manafort “allegedly misrepresented” information regarding payments he received for his lobbying work and his communications with Kilimnik. Mueller also reportedly asked witnesses about a “boat trip” Manafort took with Tom Barrack, President Trump’s longtime friend, shortly after he was ousted from the campaign in August 2016. Witnesses say they believe Mueller wanted to determine if Manafort had met up with Kilimnik on the trip, the Journal reports. Kilimnik, who was charged with Manafort this year for attempting to “influence the testimony of two witnesses” against Manafort, worked for Manafort's lobbying firm in Ukraine. Manafort was accused this week of lying to federal investigators and the FBI by special counsel Robert Mueller’s office, but no details were initially provided. The “misrepresentations” are what prompted Mueller to end Manafort’s plea deal, meaning he could face a harsher sentence than initially expected after pleading guilty to one count of conspiracy against the U.S. and one count of obstruction in September.