The House committees investigating President Trump and Ukraine have scheduled closed-door depositions for David Holmes, an official working at the U.S. Embassy in Ukraine, and Mark Sandy, an official working in the Office of Management and Budget, later this week, according to a schedule distributed to committee staff and reviewed by Axios.

Why it matters: The depositions signal that the fact-finding phase of House Democrats' impeachment inquiry is still not over, despite the first public impeachment hearings kicking off on Wednesday.

A spokesperson for the House Intelligence Committee declined to comment.

The White House did not immediately respond to a request for comment.

Holmes, the counselor for political affairs at the U.S. Embassy in Ukraine, is scheduled to appear on Friday, Nov. 15 at 3 pm.

Ambassador Bill Taylor, the top U.S. diplomat in Ukraine, testified publicly Wednesday that his staffer recently told him he overheard Trump discuss "the investigations" in Ukraine with EU Ambassador Gordon Sondland, the day after Trump's July 25 call with the president of Ukraine.

Three sources familiar with Taylor's testimony told Axios that Holmes is the staffer he was referring to.

Holmes also worked at the embassy under former U.S. Ambassador to Ukraine Marie Yovanovitch, who is scheduled to testify publicly in the impeachment hearings on Friday.

Sandy, the director of national security programs at OMB, was initially scheduled to appear before the committees on Friday, Nov. 8; however, he was a no-show. He is now listed as appearing on Sat., Nov. 16 at 10 am.

It was not immediately clear as of Wednesday morning why Sandy was put back on the schedule.

Worth noting: It isn't clear whether Holmes and Sandy have agreed to testify before the committees. The schedule solely reflects that House investigators have requested their appearance.

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Editor's note: This story has been updated to provide new reporting that reveals Holmes is staffer Taylor referenced in his public testimony on Wednesday.