"I can confirm", Morrison wrote, that the substance of the diplomat's testimony "is accurate".
The account contradicted that of Gordon Sondland, the USA ambassador to the European Union, who donated $1 million to Trump's inauguration and said no NSC officials "ever expressed any concerns" and that he didn't know Joe Biden's son Hunter was employed by Ukrainian oil giant Burisma.
Vindman said the importance of Ukraine launching an investigation into the Bidens and Burisma was also emphasized by US Ambassador to the EU Gordon Sondland in a meeting after a visit by a Ukrainian security official to Washington on July 10.
The Democrats are also calling John Eisenberg, the lawyer for the NSC who fielded an Army officer's concerns over Trump's phone call with the Ukraine president, and Michael Ellis, another security council official, according to a person familiar with the invitation and granted anonymity to discuss it. He remembered being "concerned by the call" and the idea that the President's alleged request could be seen as "partisan" and "undermine USA national security".
Bolton resigned in September, and Morrison had similarly been expected to leave for some time. "I did not think it was proper to demand that a foreign government investigate a USA citizen, and I was anxious about the implications for the US government's support of Ukraine", Vindman testified, according to a copy of his opening remarks obtained by ABC News.
"I already have good people", he said.
Last week, Cheney said Turkey must face consequences hours after the President ordered the removal of USA sanctions that were imposed October 14th.
Democrats, though, have said the witnesses are largely corroborating the central argument of the impeachment inquiry - that aid to Ukraine was being withheld as the Trump administration pushed the young democracy for the political investigation.
It's illegal to seek or receive foreign help in USA elections.
Senate Majority Leader Mitch McConnell says the resolution would deny the "most basic rights of due process" to Trump. "I can confirm that the substance of his statement, as it relates to conversations he and I had, is accurate", Morrison, who resigned Wednesday, testified in his opening statement obtained by United States media.
Lawmakers heard from Tim Morrison, who backed up an episode at the heart of the probe into U.S. President Donald Trump.
Taylor's testimony contradicted Trump's repeated denials that there was once any quid authentic quo.
He did clarify one difference from Taylor's recollection of events: He said it was his understanding that "it could be sufficient" if the new Ukraine prosecutor general, rather than Zelenskiy himself, committed "to pursue the Burisma investigation".
Mr Morrison told the committee that a diplomat had told him that Ukraine had been told outright that it would not be given military assistance unless it committed to investigating Joe Biden.
Their concerns deepened when Morrison relayed on September 7 the conversation he had with Sondland that gave him that "sinking feeling".
Like most presidential calls with foreign leaders, the Trump-Zelenskiy call was put into the T-Net system where certain individuals are granted permission to read it based on their need to know, according to two individuals with direct knowledge of the system.
The testimony comes as the Condo took its first formal vote on the impeachment inquiry Thursday, approving the draw ahead for public hearings and doable drafting of articles of impeachment. One Republican-turned-unbiased joined Democrats in approving the bundle. Only two presidents, Bill Clinton and Andrew Johnson, have been impeached, and neither was removed from office.
Over a dozen witnesses have been interviewed in the House impeachment inquiry.
They four are Congressmen Adam Schiff, the Chairman of Permanent Select Committee on Intelligence; Jerrod Nadler, the Chairman of Judiciary Committee; Eliot Engel, the Chairman of Committee on Foreign Affairs, and Carolyn Maloney, the Acting Chairwoman of the Committee on Oversight and Reform.
Democratic lawmakers want to hear next week from Bolton, the hawkish former adviser who openly sparred over the administration's approach to Ukraine - in particular, President Donald Trump's reliance on his personal attorney Rudy Giuliani for a back-channel operation.