Some 150 Blank Subpoenas Filed in Virginia Court Over Manafort's Case - Reports

The filing says all witnesses should testify in the court on July 25 during the trial and bring a number of documents stored electronically, the media reported.

Manafort is scheduled to appear before Judge Amy Berman Jackson on Friday, according to the report.

READ MORE: US Special Counsel Mueller's Approval at All-Time Low — Poll

Last week, the Office of the Special Counsel filed a third superseding indictment against Manafort and his Russian aide Konstantin Kilimnik. Both were accused of trying to obstruct justice and tamper witnesses in the time period between late February and mid-April.

Manafort has been charged with conspiracy, money laundering conspiracy, acting as an unregistered foreign agent and making false statements — all in relation to payments he received for work done the former government of Ukraine from 2006 to 2014, including for the country’s former President Viktor Yanukovych.

The Special Counsel is probing allegations that Russia interfered in the 2016 US presidential election, as well as accusations that Trump's campaign team colluded with Moscow to affect the outcome of the vote.

Russia has repeatedly refuted the allegations of interference, saying they are groundless and invented to divert public attention from actual instances of election fraud and corruption as well as other pressing issues.