The House Intelligence Committee’s 300-page report detailing Democrats case for impeaching President Donald Trump includes a rebuke of Defense Secretary Mark Esper for not providing documents related to possible wrongdoing by administration officials.

“To date, Secretary Esper has not produced a single document sought by the committees and has not indicated any intent to do so going forward, notwithstanding his public promise to ‘do everything we can to comply,’” the report states.

“Witnesses who testified before the committee have identified multiple additional documents that Secretary Esper is withholding that are directly relevant to the impeachment inquiry.”

At issue are a series of Defense Department staff readouts of meetings related to Ukraine, emails from top department officials related to delays in foriegn aid to that country, and correspondence between military and State Department officials over the issue.

Administration officials have largely refused to work with Democrats on the investigation, with Trump calling it a “witch hunt” serving purely political purposes.

In October, the Pentagon cited “legal and practical concerns” for their decision not to turn over the documents, saying that many of them could be protected by executive privilege. Officials also said they would provide the items if White House counsel waived its objections.

The report accuses Trump of withholding foreign aid to Ukraine in exchange for an investigation into corruption and the son of former Vice President Joe Biden, who is hoping to unseat Trump as president in 2020.

House Democrats have said that amounts to asking a foreign government to interfere in a domestic election. Republicans have called it part of an effort by Trump to battle corruption worldwide.

The House Judiciary Committee is holding a hearing Wednesday with outside legal experts to discuss whether the offenses outlined in the report rise to the level of “high crimes” outlined in the U.S. Constitution required for impeachment.