Bill Taylor AP Photo/J. Scott Applewhite

Bill Taylor, the acting US ambassador to Ukraine, on Thursday went to the frontlines of the conflict in eastern Ukraine.

He has emerged as a key player in the impeachment inquiry, offering one of the most damning testimonies against President Donald Trump.

Taylor corroborated the existence of an explicit quid pro quo involving Trump freezing roughly $400 million in military aid to Ukraine and his requests for certain investigations.

He has also excoriated the decision to withhold the military aid, describing it as harmful to US national security and a move that could embolden Russia to be even more aggressive toward Ukraine.

The Vietnam veteran turned diplomat will offer the first public testimony in the impeachment inquiry on Wednesday.

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The top US diplomat to Ukraine, Bill Taylor, on Thursday visited the frontlines of Ukraine’s conflict with pro-Russian separatists — less than a week before he’s set to offer the first public testimony in the impeachment inquiry.

Taylor was joined by Andriy Yermak, a top aide to Ukrainian President Volodymyr Zelensky, in his visit to the conflict zone. Yermak is also at the center of the impeachment inquiry as his name has come up in testimony in relation to the broad efforts from President Donald Trump and his allies to pressure Ukraine into launching certain investigations.

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Андрій Єрмак, представники українського уряду та посли іноземних держав відвідали українські позиції в районі населеного пункту Богданівка (Петрівське) Донецької області, де має відбутися черговий етап розведення сил і засобів.

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Taylor has already testified to House investigators behind closed-doors, providing a damning picture of Trump’s dealings with Ukraine — particularly regarding the president’s move to freeze $400 million in military aid to the country as it continues to battle pro-Russian separatists in the Donbas region.

A transcript of Taylor’s testimony was released by the House committees spearheading the impeachment inquiry on Wednesday.

Taylor corroborated the existence of an explicit quid pro quo involving Trump freezing roughly $400 million in military aid to Ukraine and his requests for an inquiry into former Vice President Joe Biden, as well as a conspiracy theory on the 2016 election.

„That was my clear understanding, security assistance money would not come until the President [of Ukraine] committed to pursue the investigation,“ Taylor said to House investigators, according to the transcript.

‚More Ukrainians would undoubtedly die without US assistance‘

Taylor in his testimony also excoriated the decision to withhold the military aid, describing it as harmful to US national security and a move that could embolden Russia to be even more aggressive toward Ukraine.

In his opening statement, Taylor described a visit to the frontlines in northern Donbas over the summer in vivid terms that underscored his views on the importance of US security assistance to Ukraine.

„I could see the armed and hostile Russian-led forces on the other side of the damaged bridge across the line of contact,“ Taylor said. „Over 13,000 Ukrainians had been killed in the war, one or two a week. To this day, that continues. More Ukrainians would undoubtedly die without US assistance.“

A career diplomat with a distinguished record of public service, Taylor is also a US Army veteran who served in the Vietnam War. Among other diplomatic postings, Taylor was the US ambassador to Ukraine from 2006 to 2009. He’s set to return to Washington to testify in the first open hearing of the impeachment inquiry on Wednesday.

The Ukraine conflict began in 2014 and has led to roughly 13,000 deaths and displaced roughly 1.5 million people.