Prosecutors allege that Paul Manafort was working on Ukrainian political matters in 2018, after his indictment in the special counsel's investigation, and also revealed that a former business associate of his who was assessed by the FBI to have ties to Russian intelligence attended President Trump's inaugural, according to new court filings.

The details came in a partially redacted transcript released Thursday of a sealed hearing between prosecutors and the defense team for Trump's former campaign chairman in the ongoing legal battle over whether Manafort lied and breached his deal to cooperate in Robert S. Mueller III's probe of Russian interference in the 2016 election, according to The Washington Post.

The transcript contained some new elements.

At the hearing, attorneys discussed whether Manafort may have been motivated to lie in one unspecified instance "to at least augment his chances for a pardon," the transcript states.

In another instance during the hearing, prosecutor Andrew Weissmann alleged Manafort may have lied to hide a scheme to funnel cash to himself while doing unpaid work for the Trump campaign.

If a judge determines Manafort lied after his plea, it could affect the sentencing he would receive after his admission that he conspired to defraud the United States, violate lobbying laws and obstruct justice in connection with years of undisclosed work for a pro-Russian political party and Ukrainian politician Viktor Yanukovych. He also was convicted by a jury in August in a separate federal case in Virginia for bank and tax fraud crimes.

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Manafort and Konstantin Kilimnik – the aide who also has been indicted in the Mueller investigation – discussed a peace plan for Ukraine on more than one occasion, including during one meeting in August 2016, while Manafort served as Trump's campaign chairman, Manafort's attorneys have said.

The pair also met in December 2016, in January 2017 when Kilimnik was in Washington and again in February 2017, and as recently as the winter of 2018, U.S. District Judge Amy Berman Jackson summarized at the hearing, the transcript shows.

Jackson has not decided if Manafort lied and has set another closed hearing for Wednesday to weigh further arguments about Manafort's truthfulness while shielding sensitive information about active investigations and uncharged individuals.

Mueller's office claims Manafort "intentionally provided false information" in debriefing sessions on several topics, such as his interactions with Kilimnik. Court documents show that prosecutors contend Manafort passed polling data related to the presidential campaign to Kilimnik during the campaign, and that the two worked on a poll in Ukraine in 2018.