The Trump administration directed the U.S. ambassador to the European Union Gordon Sondland not to appear for a scheduled deposition with House Democrats on Tuesday, according to the New York Times.

Why it matters: Democrats want to question Sondland about his role in President Trump's pressure campaign on Ukraine to open an investigation into former Vice President Joe Biden and Biden's son, Hunter.

The Trump administration gave the order just hours before Sondland was scheduled to sit for a deposition in the Capitol, and House Democrats have warned that they will consider any attempts by the administration to interfere with their investigation as obstruction, possible grounds for impeachment.

Context: Sondland and the former U.S. envoy to Ukraine Kurt Volker reportedly drafted a statement in August that would have committed Ukrainian President Volodymyr Zelensky to investigating the Ukrainian energy company that once counted Hunter Biden as a board member.

Both Sondland and Volker were both named in the whistleblower complaint that is now at the center of the Trump impeachment inquiry.

Volker testified before a group of House committees last week, claiming no knowledge of any Trump administration push to pressure Ukraine. He also release text messages that featured conversations between him, Sondland and Bill Taylor, the top U.S. diplomat to Ukraine.

What they're saying: Sondland's legal counsel released a statement saying he "is profoundly disappointed that he will not be able to to testify today."

"Ambassador Sondland believes strongly that he acted at all times in the best interests of the United States, and he stand ready to answer the Committee's questions fully and truthfully."

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