Paul Manafort, President Donald Trump's former campaign chairman, leaves the Federal District Court after a hearing, in Washington, May 23, 2018. Credit: Jose Luis Magana | AP

A federal judge Tuesday said prosecutors working for Special Counsel Robert Mueller must offer more details about the lies they claim former Trump campaign chairman Paul Manafort has told them, even as defense attorneys said they might not contest that Manafort broke his plea deal.

Prosecutors said in a court filing Friday that Manafort, 69, lied repeatedly in the course of 12 interviews with investigators and two appearances in front of Mueller’s grand jury conducted since he pleaded guilty in September.

They redacted much of the filing from public view and wrote in broad generalities about some topics. U.S. District Judge Amy Berman Jackson told prosecutors on Tuesday that the government’s filing did not provide enough information for her to determine that Manafort has breached the plea deal that requires him to fully cooperate with prosecutors.

Referring to the filing, Jackson said, “while it sufficed . . . to put me and the defense on notice of the subject matter areas in dispute, it doesn’t provide me with sufficient information to enable me to make factual findings that your allegations are correct.”

Manafort’s lawyers told her it was increasingly possible the defense might not ask for a hearing to challenge the government’s allegations. They have previously said Manafort believes he has been truthful.

Defense attorney Richard Westling said that a breach might not impact prosecutors’ sentencing recommendation, in which case Manafort might not challenge the assertion he had broke the deal.

“If we reach a place where the effect is not something we have a problem with,” Westling said, “it’s possible within the very near term we may inform the court after talking to our client that we don’t feel the need for the hearing.”

Jackson expressed surprise on that point, saying, “It seems unlikely to me this is going to be irrelevant.”

She added: “I don’t want to get to sentencing and have them say, he wasn’t truthful, and have you tell me he was. I get the feeling they’re going to want me to know whether he was truthful or not truthful with them when I think about sentencing him,” and whether to credit him for any cooperation.

Jackson directed both sides to continue talks but told Manafort’s lawyers to tell her by Jan. 7 if they want a hearing to challenge whether he broke the deal.

If they want the hearing, prosecutors would then come back a week later to detail the lies they contend Manafort told and a hearing to address the two positions would occur Jan. 25, Jackson said.

In their filing Friday, prosecutors said Manafort lied about his interactions with a Russian employee of his political consulting firm who the FBI assessed as having ties to Russian intelligence, as well as his ongoing contacts with Trump administration officials. Konstantin Kilimnik, who worked for Manafort starting in 2005 and met with him in the U.S. twice while Manafort was working for Trump, has been charged with working with Manafort to obstruct Mueller’s investigation. He is believed to be in Moscow.

Prosecutors said Manafort also lied about the circumstances of a $125,000 wire transfer in 2017. Many details of his alleged lies were redacted by prosecutors from public view on the grounds that they deal with the special counsel’s ongoing investigation.

Manafort was convicted of tax and bank fraud charges in Virginia in August. He pleaded guilty in September to additional charges, including conspiring to defraud the United States by hiding years of income and failing to disclose lobbying work for a pro-Russian political party and politician in Ukraine.

The plea deal was intended to allow him to skip a second trial in Washington and offer him leniency in sentencing. But it required that he provide truthful testimony to prosecutors.

Manafort is confined to the Alexandria, Virginia, jail while he awaits sentencing in March. He declined the opportunity to attend Tuesday’s hearing.