A federal judge said she intends to rule no later than the end of the day Monday on whether former White House counsel Donald McGahn must testify under subpoena to Congress, after the House Judiciary Committee asked her to accelerate a decision because it aims to call him after the current round of public impeachment hearings finish in December.

U.S. District Judge Ketanji Brown Jackson of Washington entered an order Tuesday about her deadline intent “absent unforeseen circumstances” shortly after a filing from House General Counsel Douglas N. Letter arguing last week’s opening of the hearings before the House Intelligence Committee was grounds for urgency.

Those committee hearings are exploring President Trump’s request that Ukraine investigate former vice president Joe Biden — a potential 2020 political rival — and his son Hunter Biden. House Democrats are debating whether articles of impeachment should include obstruction of justice allegations detailed in the special counsel report by Robert S. Mueller III.

“Given that the House’s impeachment inquiry is proceeding rapidly, the Committee has a finite window of time to effectively obtain and consider McGahn’s testimony,” Letter wrote.

“The Judiciary Committee anticipates holding hearings after [the] public hearings have concluded and would aim to obtain Mr. McGahn’s testimony at that time,” Letter wrote.

The House sued Aug. 7 to enforce its April subpoena of McGahn. The White House has directed McGahn not to comply, claiming that the former counsel is “absolutely immune from compelled congressional testimony.”

Jackson fast-tracked proceedings on the House suit and held an Oct. 31 hearing at which she told both sides that she hoped to issue a ruling after completing a two-week trial, which ended Friday.

In his filing, Letter reminded the judge that she promised to expedite a decision over the White House’s blanket assertion that current and former top presidential aides cannot be forced to answer questions or turn over documents to lawmakers.

House Democrats call McGahn, a key figure in Mueller’s investigation, one of the “most important” witnesses of possible obstruction of justice by Trump.

McGahn’s statements are mentioned more than 160 times in the 448-page final report prepared in the special counsel’s probe of Russian interference in the 2016 U.S. election.

Mueller’s report ultimately concluded that it was not the special counsel’s role to determine whether the president broke the law.

McGahn’s case was the first lawsuit Democrats filed to force a witness to testify since they regained control of the House after the 2018 midterm elections, and has become one of several major political and legal battles between Congress and the Trump White House over the Constitution’s balance of powers.

Sure to be appealed by whichever side loses, the case also is expected to set a major separation-of-powers precedent for other impeachment-related testimony by witnesses summoned by House Democrats.

In its court filing Tuesday, the House echoed statements it gave a day before that the Judiciary Committee is continuing to investigate “instances of misconduct recounted in the Mueller Report, including episodes in which McGahn was involved,” to consider potential articles of impeachment in addition to Ukraine-related charges.

William A. Burck, McGahn’s attorney, has said that McGahn will abide by the president’s instructions absent a court reversal. McGahn “has an ethical obligation to protect client confidences,” Burck said. “Don does not believe he witnessed any violation of law. And the president instructed Don to cooperate fully with the special counsel but directed him not to testify to Congress unless the White House and the committee reached an accommodation.”