Former Trump campaign chairman Paul Manafort will plead guilty in federal court Friday as part of a plea agreement with Special Counsel Robert Mueller, Fox News has learned.

A plea agreement hearing is set for Friday morning. It's not known whether Manafort has agreed to cooperate with prosecutors.

But according to Politico, the plea deal includes a 10-year-cap for how long Manafort will be in prison. It also includes allowing Manafort to serve his time for both trials concurrently.

Manafort, in a trial set to begin Sept. 24, is facing seven counts of foreign lobbying violations and witness tampering in federal court in Washington. 

In August, in a separate trial in Virginia, a federal jury found Manafort guilty on eight counts of federal tax and banking crimes.

The case was brought by Mueller's team, which is probing potential crimes related to the 2016 election. But Manafort has not been charged with anything related to the campaign.

In August, Manafort's bank and tax fraud conviction made him the first campaign associate of Trump found guilty by a jury as part of Mueller's probe.

"I feel very badly for Paul Manafort," Trump told reporters after the August verdict, adding that it had "nothing to do with Russian collusion."

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