(CNN) The House Judiciary Committee is moving forward with its plan for staff attorneys to question Attorney General William Barr at a Thursday hearing on special counsel Robert Mueller's investigation, even as the attorney general is threatening not to attend the hearing over the proposed format.
House Judiciary Chairman Jerry Nadler, a New York Democrat, scheduled a Wednesday committee vote to allow an additional hour of questioning at Thursday's hearing. The vote would allow members or staff to question Barr during the extra hour, which would be divided between Democrats and Republicans.
Barr has objected to the format that would have staff asking questions, raising the prospect he won't appear on Thursday. But Nadler told reporters Monday the issue wasn't up for negotiation.
"There is no middle ground," Nadler said. "It's none of the business of a witness to try to dictate try to a congressional committee what our procedures for questioning him are."
Nadler added that the Justice Department seemed to be "very afraid" to have Barr answer questions from committee staff.
Barr is testifying before the Republican-led Senate Judiciary Committee on Wednesday, and is supposed to appear before Nadler's panel on Thursday, where he agreed to testify voluntarily. Justice Department spokesperson Kerri Kupec said Sunday, "The attorney general agreed to appear before Congress. Therefore, Members of Congress should be the ones doing the questioning. He remains happy to engage with Members on their questions regarding the Mueller report."
Democrats are still planning to hold their hearing Thursday even if Barr doesn't show, Nadler said, meaning there could be visuals of a literal empty chair.
If Barr were to skip the hearing, it would mark a major escalation in the dispute between the committee and the Trump administration. Nadler and other House Democrats have criticized Barr's handling of the end of the Mueller investigation, and Nadler has issued a subpoena to obtain the unredacted report and Mueller's underlying evidence.
Nadler's staff met Monday with Justice Department staff about the committee's demand to get the full Mueller report, but Nadler said afterward there was no significant progress on the effort to get the full report.
The committee has set a deadline of Wednesday for the Justice Department to comply with the subpoena to turn over the full unredacted report.
For Thursday's hearing, Nadler is proposing that lawmakers each get a five-minute round of questions. Following that, Democratic and Republican staff counsels would each have a half-hour period that would allow for more detailed questioning of the attorney general.
Nadler spokesman Daniel Schwarz said committee staff have asked questions at Judiciary Committee hearings in the past, including at impeachment proceedings for former Presidents Richard Nixon and Bill Clinton. Committee staff also asked questions in closed-door interviews during the Republican-led investigation into the Justice Department and FBI's handling of the Hillary Clinton and Russia investigations.
A Republican Judiciary Committee spokesperson criticized Nadler for fighting with Barr over the format, arguing the attorney general voluntarily agreed to testify and there's no precedent for having staff interview witnesses at an oversight hearing that's not part of an impeachment proceeding.
The dispute with Barr is hardly the only fight that Nadler is waging with the Trump administration. Nadler has also issued a subpoena for former White House counsel Don McGahn to testify next month about whether Trump obstructed justice.
McGahn hasn't said yet whether he will testify, and the White House may seek to prevent McGahn from complying with the subpoena and cite executive privilege.
Nadler said Sunday that he expected McGahn to testify, arguing he waived executive privilege when he spoke to Mueller.
"The President says he doesn't want people talking about certain things, but they have already talked about those things to Mueller and to others. So that means if there was any executive privilege it's been waived, you cannot waive the privilege and then reassert it," Nadler said. "So there is no legal excuse whatsoever ... The only question is how long they will draw it out in court before the subpoena is followed, and how contemptuous of Congress this administration will be."
This story has been updated with additional developments Monday.