The House Budget and Appropriations Committees sent a demand to the White House’s Office of Management and Budget on Friday for reams of documents related to the Trump administration’s delay in disbursing $400 million in aid to Ukraine.

The document demand comes as House Democrats enter into an impeachment inquiry against President Trump over his attempt to pressure the Ukrainian government to manufacture helpful political information.

The two panels initially expressed “serious concerns” in a Sept. 18 letter that withholding the aid was an “abuse of authority.”

Citing this week’s release of a record of a July 25 phone call between Trump and Ukrainian President Volodymyr Zelensky, as well as an Aug. 12 whistleblower report, the concealment of which set Washington ablaze, the panels accuse the White House of “impeding” the government from using congressional appropriations, and of illegally retaining the money.

“These actions have collectively undermined the longstanding application and predictability of federal funds management processes and require closer examination by our committees to inform appropriate legislative responses and reforms,” the letter reads.

The panels gave the White House an Oct. 1 deadline to reply to a list of questions, and an Oct. 11 deadline to supply documents.

Read the letter here: