FILE PHOTO: U.S. Ambassador to the EU Gordon Sondland poses ahead of a meeting with European Commission President Jean-Claude Juncker and White House senior adviser Jared Kushner (unseen) at the EU Commission headquarters in Brussels, Belgium, June 4, 2019. REUTERS/Francois Lenoir Reuters

Gordon Sondland, the US ambassador to the European Union, became the latest witness in the impeachment inquiry to confirm an explicit quid pro quo between the Trump administration and Ukraine.

Sondland confirmed to Congress that the administration leveraged military aid to Ukraine for investigations into former Vice President Joe Biden and his son Hunter.

A transcript of Sondland’s testimony released Tuesday said he described the pressure to investigate the Bidens as „insidious“ and „improper.“ When asked whether he thought it was illegal, he said, „I’m not a lawyer, but I assume so.“

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Gordon Sondland, the US ambassador to the European Union, became the latest witness in the impeachment inquiry into President Donald Trump to confirm that the administration leveraged military aid for investigations into former Vice President Joe Biden, a political rival, and his son Hunter.

The three House committees pursuing the impeachment inquiry on Tuesday released excerpts from the closed-door testimony last month of Sondland and Kurt Volker, the former US special envoy for Ukraine.

Sondland made a fortune as a successful hotel executive and entrepreneur in the Pacific Northwest and became a generous donor to Republican politicians — which included giving $1 million to Trump’s 2017 inaugural fund. In 2018, Trump nominated Sondland to be the US‘ ambassador to the European Union.

Sondland acknowledged in one line of questioning that the pressure on Ukraine to investigate the Bidens became increasingly „insidious.“

In an addendum he submitted to the committees dated Monday, Sondland said the testimony of other witnesses, including Volker and Bill Taylor, the acting ambassador to Ukraine, refreshed his memory that foreign aid was withheld.

From the transcript:

Q: There were demands, weren’t there, that an investigation take place of 2016 or Burisma? Ultimately those were demands, were they not?

A: Ultimately, yes.

Q: And it’s fair to say that you had to navigate those demands, you had to accommodate what the President and his lawyer wanted, if you were going to set up this meeting you thought very important?

A: I think that’s fair …

Q: But I think you said, Ambassador, that over time things got more and more insidious. I think those were your words. It started out with no condition, and then there was a condition for an investigation into the corruption, and then there was a condition of an investigation into 2016 and Burisma, and then on the call itself it became clear the condition was an investigation of 2016 and the Bidens. I think you described that as becoming more and more insidious, correct?

A: That’s correct.

He later said it was „improper“ for the Trump administration and Trump’s personal attorney Rudy Giuliani to push Ukraine to investigate the Bidens. When a lawmaker asked whether Sondland also believed it was illegal, he replied, „I’m not a lawyer, but I assume so.“

The inquiry centers on the claims in an anonymous whistleblower’s complaint that Trump was „using the power of his office to solicit interference from a foreign country“ in the 2020 US election in a series of events culminating in a July 25 phone call with Ukrainian President Volodymyr Zelensky.

The complaint specifically charged that Trump’s pressure on the Ukrainian government to investigate the Bidens came days after he withheld a nearly $400 million military-aid package to Ukraine that Congress had already appropriated.

Giuliani has for months been pushing an unsubstantiated theory that Joe Biden, as vice president, called for the firing of a Ukrainian prosecutor who was investigating the oil-and-gas company Burisma Holdings, where Hunter Biden served on the board from 2014 to 2019, to help his son.

The whistleblower’s complaint has been corroborated by the White House’s summary notes of the July 25 call, White House officials, and the sworn testimony of several career diplomatic and national-security officials.

The White House’s notes of the call said Trump brought up how the US does „a lot for Ukraine,“ then asked Zelensky to do him a „favor, though,“ by investigating the Bidens and a debunked conspiracy theory that Ukraine has a Democratic National Committee server.

For several weeks, the White House and Republicans‘ main defense was arguing that Trump was not engaged in a quid pro quo with Ukraine.

But Mick Mulvaney, the acting White House chief of staff, appeared to tell reporters last month that the administration engaged in a quid pro quo with Ukraine by trading US military aid for investigations.

„Did he also mention to me in the past the corruption related to the DNC server? Absolutely. No question about that,“ Mulvaney said of Trump. „But that’s it. And that’s why we held up the money.“

Mulvaney later tried to walk back his comments, but the damage to that defense was done.

Another top National Security Council official working on Ukrainian and Eastern European affairs, Tim Morrison, has also confirmed previous testimony, saying he learned that „the release of the security sector assistance might be conditioned on a public statement reopening the Burisma investigation“ from Ukraine.