Prosecutors have accused Manafort and Kilimnik of attempting to sway the testimony of two potential witnesses who might offer evidence against Manafort.
The indictment, filed in Washington, D.C., charges Manafort and Kilimnik with obstruction of justice and conspiracy to obstruct justice. He joined the Russian Army as a translator, work that closely aligned him with the army's intelligence services - an account pieced together from a handful of people who worked with him or were briefed on his background, including a former senior CIA official with direct knowledge of Kilimnik's activities.
Manafort's lawyers responded to those allegations in a sharply worded filing late Friday, accusing Mueller of contriving "dubious allegations" of witness tampering and, in so doing, poisoning the jury pool ahead of his trials.
The Manafort case though focuses on his work between 2004 and 2014 in Ukraine for pro-Russia politicians including former Ukraine president Viktor Yanukovych.
He was described as the intermediary through which Manafort volunteered to brief his onetime client, aluminum tycoon Oleg Deripaska, about the Trump campaign. "Or to put it even more bluntly than Mueller: Donald Trump's campaign chairman had a pawn of Russian intelligence as his indispensable alter ego", the Atlantic's Franklin Foer wrote Wednesday. These entities were in a previous Manafort indictment, and Mueller is alleging that they are connected to Manafort's grand money laundering scheme.
Earlier this week, Trump tweeted that Manafort "came into the campaign very late and was with us for a short period of time".
"Manafort and Kilimnik repeatedly contacted Persons D1 and D2 in an effort to secure materially false testimony", prosecutors alleged in court papers.More news: Sampaoli calls up Enzo Perez to replace injured Lanzini
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Paul Manafort leaves the E. Barrett Prettyman Federal Courthouse in Washington, D.C. on February 28, 2018.
Manafort has maintained his innocence despite all of the charges brought before him.
The charges mark the second time since October that an indictment against Manafort has been amended to include additional allegations.
Manafort was exercising his freedom to disagree with the special counsel's legal theories, the attorneys said.
The witnesses have told investigators that they believed Manafort and Kilimnik were trying to get them to lie about the nature of his Ukrainian political work.
Asked on Friday if he would pardon Manafort, Trump refused to answer. The previously pending charges against Manafort of course had nothing to do with the synthetic collusion hyseteria over the 2016 election.
Kilimnik has also drawn the scrutiny of congressional committees investigating Russian interference in the 2016 presidential campaign. Kilimnik also allegedly sought to contact witnesses in April.