State Department official George Kent, a key witness in the impeachment inquiry of President Donald Trump, told House investigators last month that he had written contemporaneous memos of specific conversations he'd witnessed related to an attempted quid pro quo with Ukraine that he said were "injurious to the rule of law" in both countries, according to a transcript of his testimony made public Thursday.

"I wrote a note to the file saying that I had concerns that there was an effort to initiate politically motivated prosecutions that were injurious to the rule of law, both in Ukraine and the U.S.," Kent told the committees last month of two particular conversations he witnessed.

Lawmakers have focused on Kent, a deputy assistant secretary of state who worked on Ukraine and five other countries, and other witnesses to establish that the Trump administration had froze aid intended for Ukraine as part of an attempt to pressure it to open probes that would benefit Trump politically.

According to the transcript, Kent shared with lawmakers multiple instances in which he conveyed to other government officials his grave concerns about the White House's efforts to have Ukraine launch investigations into Burisma Holdings — the Ukrainian gas company that former Vice President Joe Biden's son Hunter joined as a board member in 2014 — and a conspiracy theory about alleged Ukrainian interference in the 2016 election.

He recalled telling Catherine Croft, a special adviser for Ukraine, on Aug. 15, "if you' re asking me, have we ever gone to the Ukrainians and asked them to investigate or prosecute individuals for political reasons, the answer is, I hope we haven't, and we shouldn't because that goes against everything that we are trying to promote in post Soviet states for the last 28 years, which is the promotion of the rule of law."

Kent later told investigators that he informed Bill Taylor, the top U.S. diplomat in Ukraine, that when it came to the investigations desired by Trump and his personal attorney, Rudy Giuliani, "that's wrong, and we shouldn't be doing that as a matter of U.S. policy."

He also told the chairs plainly that, "I do not believe the U.S. should ask other countries to engage in politically associated investigations and prosecutions."

Later in his testimony, however, Kent said it was his “personal opinion” that the delivery of the military aid had been linked to granting a White House visit to Ukrainian President Volodymyr Zelenskiy — and not the aid.

NBC News reported last month that Kent told investigators that acting White House chief of staff Mick Mulvaney tapped three other Trump administration officials — Energy Secretary Rick Perry, U.S. Ambassador to the European Union Gordon Sondland and Kurt Volker, the then-U.S. special envoy to Ukraine — to oversee U.S. policy in Ukraine, sidelining experienced State Department officials. The trio, who Kent testified called themselves "the three amigos," elbowed all other officials out of the way, according to lawmakers in the room.

The transcript of Kent's closed-door testimony before the three House committees leading the impeachment inquiry into Trump was just the latest document made public this week as the probe moves to a public phase. House Democrats have released transcripts of testimony from Sondland, Volker, Taylor and Marie Yovanovitch, the ousted U.S. ambassador to Ukraine.

The transcripts from those key figures have largely established a narrative that suggests Trump directed officials to tie nearly $400 million in military and security aid to Ukraine to demands that Zelenskiy announce probes into the Bidens and the 2016 election.

This week, Sondland made a significant change to his testimony: He said he now remembers telling a top aide to Zelenskiy that Ukraine would not receive U.S. military assistance until it committed to investigating the 2016 election and Joe Biden.

Sondland had no diplomatic experience before Trump nominated him in 2017 to become ambassador to the E.U., which does not include Ukraine. He was a wealthy hotelier who donated about $1 million to Trump’s inaugural committee and referred to himself in his prepared testimony as a “lifelong Republican.”

Kent's testimony, according to the transcript, appeared to corroborate large chunks of that narrative.

The Government Accountability Office said Thursday that, at the request of Sen. Chris Van Hollen, D-Md., it had opened a review of the Trump administration's decision to hold up the aid to Ukraine. The Wall Street Journal was first to report that the nonpartisan congressional watchdog was probing the matter.

Trump has repeatedly denied engaging in a quid pro quo with Ukraine.

In his testimony, Kent also took aim at Giuliani for his role in leading a smear campaign against Yovanovitch.

Giuliani “had been carrying on a campaign for several months full of lies and incorrect information” — and his “assertions and allegations against former Ambassador Yovanovitch were without basis, untrue, period,” Kent said, according to the transcript.

Yovanovitch departed Ukraine in May, months ahead of her scheduled departure, after coming under attack from right-wing media, which alleged she was hostile to the president. Her departure set off alarm bells among Democrats in Congress, but the State Department said at the time her exit was planned.

Yovanovitch testified to House investigators on Oct. 11 that Trump had personally pressured the State Department to remove her, even though a top department official assured her that she had "done nothing wrong."

In Trump's July 25 phone call with Zelenskiy, Trump referred to Yovanovitch as "bad news." That call is at the heart of the intelligence community whistleblower complaint that touched off the impeachment inquiry.

In a statement, the chairs of the three committees leading the inquiry — House Intelligence Committee Chair Adam Schiff, D-Calif.; House Foreign Affairs Committee Chair Eliot Engel, D-N.Y.; and House Oversight Committee acting Chair Carolyn Maloney, D-N.Y. — said Kent’s testimony “strongly corroborates testimony from numerous other witnesses” and “affirms that he and his colleagues recognized the impropriety of pressuring Ukrainian officials to undertake politically motivated investigations to help President Trump’s re-election prospects in 2020.”

The chairs also note that Kent’s “contemporaneous documentation of conversations and events” — which are property of the State Department — have not been turned over by the agency, despite a subpoena.

“The State Department and White House continue to withhold these key documents from the committees in defiance of duly authorized subpoenas. These actions demonstrate the president’s clear obstruction of Congress and support the inference that these documents further corroborate the testimony of presidential misconduct that we have received,” the chairs said.

Kent is slated to be one of the witnesses testifying on Nov. 13 in the first open impeachment inquiry hearing.