National Security Council Director for European Affairs Alexander Vindman arrives for a closed-door deposition at the US Capitol in Washington, DC on October 29, 2019.

Mandel Ngan | AFP | Getty Images

Army Lieutenant Col. Alexander Vindman testified in the House impeachment inquiry that there was "no ambiguity" that a U.S. ambassador had called on Ukraine to investigate former Vice President Joe Biden and his son in order to secure a sought-after meeting at the White House.

Vindman, a top Ukraine expert in the National Security Council, had testified behind closed doors in late October as part of the investigation into the Trump administration's efforts to have Ukraine investigate the Bidens and the 2016 presidential election.

House impeachment investigators released the full 340-page transcript of Vindman's testimony Friday.

During his deposition, Vindman recalled a conversation in which Gordon Sondland, the U.S. ambassador to the European Union, talked to Ukrainian officials about what was needed "in order to get the meeting" at the White House.

"I mean, there was no ambiguity, I guess, in my mind. He was calling for something, calling for an investigation that didn't exist into the Bidens and Burisma," Vindman said, referring to Burisma holdings, the Ukrainian natural gas company where Biden's son Hunter had served as a board member.

Vindman's testimony described in detail a monthslong pressure campaign orchestrated by a small group of Trump administration officials this spring and summer to get Ukraine to agree to launch investigations that could benefit Trump's reelection effort.

"I thought it was wrong. I thought it was wrong to call — to basically have — to organize a situation in which you're asking a foreign power to investigate a matter," Vindman said. He also noted that while he thought it was "inappropriate," he did not believe he was reporting a crime by bringing it to others' attention.

Vindman also details how Sondland described White House acting chief of staff Mick Mulvaney's involvement in the effort.

As the top Ukraine expert at the NSC, Vindman also listened in on the July 25 telephone call between Trump and Ukrainian President Volodymyr Zelensky which is now at the heart of the House impeachment inquiry. During that call, Trump asked Zelensky for "a favor" and proceeded to describe the investigations he wanted Ukraine to undertake.

In his testimony, Vindman documented a series of alarms he said were raised earlier this year by national security professionals in the White House, including him, who were aware of a shadow foreign policy toward Ukraine.

Vindman said that in July he reported two separate incidents to the top lawyer at the NSC.

The first was a July 10 meeting during which Vindman said Sondland told a group of visiting Ukrainian officials that in order for Zelensky to secure a meeting with Trump, he must first commit to undertaking two investigations. One was into a Ukrainian company, Burisma, on whose board the son of Trump's political rival, former Vice President Joe Biden, once sat. The second concerned a discredited conspiracy theory alleging that Ukraine, and not Russia, interfered in the 2016 U.S. presidential election.

"So I heard him say that this had been coordinated with White House Chief of Staff Mr. Mick Mulvaney," Vindman said in the testimony. When an investigator asked what Sondland said about Mulvaney, Vindman said: "He just said he had had a conversation with Mr. Mulvaney, and this is what was required to get a meeting."

Following that July 10 meeting, Vindman testified that he told Sondland "that his statements were inappropriate, that the request to investigate Biden and his son had nothing to do with national security, and that such investigations were not something the NSC was going to get involved in or push."

Two weeks later, Vindman said, he had many of the same concerns after listening to the July 25 call between Trump and Zelensky.

"I did not think it was proper to demand that a foreign government investigate a U.S. citizen, and I was worried about the implications for the U.S. government's support of Ukraine," he testified on Oct. 29. Following that call, Vindman again reported his concerns to the NSC's lead counsel.

Vindman is an Iraq war veteran and a Purple Heart recipient whose family fled the Soviet Union when he was a child. But following the release of his opening statement late last month, several conservative pundits sought to smear Vindman by questioning his loyalty to the United States and openly wondering whether he was a Ukrainian operative.

The House impeachment probe focuses on whether Trump abused the power of his office in his attempt to pressure Ukraine to investigate a political rival, and if so, whether those actions meet the standard for "high crimes and misdemeanors" deserving of impeachment and, potentially, removal from office.