Special counsel Robert Mueller on Wednesday filed a request for 100 blank subpoenas in the Eastern District of Virginia, where former Trump campaign chairman Paul Manafort is facing trial for bank and fraud charges.

This is in addition to a court filing in June, when Mueller's team filed a request for 150 blank subpoenas, or 75 possible witnesses.

The 100 blank subpoenas amount to 50 total possible subpoenas — in each case, a subpoena is needed for the witness and another is needed for the defense.

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Court documents filed in April show that Mueller's team was pushing to subpoena 35 witnesses in the trial. Then in May, court documents showed he had filed 70 blank subpoenas.

A blank subpoena means the party serving the subpoena, in this case the federal government, can fill in the name later, as long as it is done so before the subpoena is served.

The two-page filing Wednesday reveals little, but says that that each subpoena recipient must appear in the Alexandria, Va., courthouse on July 25 at 10 a.m. to testify in the case.

The request for subpoenas comes amid an effort by Manafort’s defense team to delay the trial and move it from Alexandria, Va. to Roanoke, Va.

Prosecutors with Mueller’s team said Wednesday that the trial should not be postponed or moved, describing how Manafort has made hundreds of phone calls to his lawyers, and is being treated like a “VIP” in the Northern Neck Regional Jail in Warsaw, Va.

Manafort, 69, was sent to jail last month by the federal judge overseeing his case in Washington for allegations of witness tampering. That trial is set to begin Sept. 17.

Last week, Manafort’s lawyers said in a court filing their client was "locked in his cell for at least 23 hours per day" in " solitary confinement.” That, plus the distance of the jail from his lawyers, "makes it effectively impossible for Mr. Manafort to prepare" for the two trials, they said in arguing for his transfer from the Northern Neck Regional Jail.

However, Manafort withdrew his request Tuesday to transfer to a detention center in Alexandria. The judge overseeing the Alexandria case, T.S. Ellis III, declined the request on Wednesday, and ordered Manafort be moved to behind bars in Alexandria.

Ellis also ordered lawyers for Mueller and Manafort to court Tuesday for oral arguments on whether to move the trial location or to delay it.