Special counsel Robert Mueller believes Paul Manafort misled his team in statements about his business dealings and his communications with a former Ukrainian associate, Konstantin Kilimnik, The Wall Street Journal reported.

According to people familiar with the matter who spoke to WSJ, the “lies” that Mueller alleged in a court filing this week “don’t appear” to be related to the Russia probe, in the WSJ’s words.

Kilimnik was charged alongside Manafort earlier this year for attempting to influence key witnesses in the case against Manafort for his financial dealings. Mueller’s team is alleging that Manafort lied to investigators about his contacts with Kilimnik when the two allegedly discussed the coordination of their testimony.

Manafort also reportedly gave Mueller false information about money he received for his lobbying work, according to the WSJ’s sources.