The original 10-hour October 17 deposition by Sondland, a donor to President Trump, came under intense scrutiny in recent weeks as other impeachment witnesses offered testimony that seemed to conflict with what Sondland said under oath last month.
The US envoy previously denied any politically motivated aid freeze.
"Based on evidence gathered in the impeachment inquiry and public reporting, we believe that you possess substantial first-hand knowledge and information relevant to the House's impeachment inquiry", the Democratic chairmen of the three committees conducting the inquiry wrote to Mulvaney. Sondland knows that proposed arrangement to be a fact, he said, because he was the one who carried the message to a Ukrainian official on the sidelines of a conference in Warsaw with Vice President Mike Pence.
Sondland told Yermak "that resumption of U.S. aid would not likely occur until Ukraine provided the anti-corruption statement that we had been discussing for weeks", he told investigators.
Sondland's new testimony, which was included in the public release of his closed-door deposition transcript on Tuesday, adds to Democrats' evidence that U.S. President Donald Trump connected the freezing of $400 million in U.S. security aid to Ukraine to investigations into the 2016 election and former Vice President Joe Biden. Grisham said that Sondland "did not know" when or by whom the aid was suspended and that he "presumed" there was a link to the aid.
William Taylor, the acting United States ambassador to Ukraine, had repeatedly questioned Mr Sondland in text messages about a quid pro quo, a Latin phrase meaning an exchange of favours. Mr Taylor had asked.
Volker said Trump described Ukrainians as "all corrupt, they are all bad people" and that they had "tried to take me down" in the 2016 election.
Sondland claimed that he stopped by Hill's office a few days before she was set to leave the White House and that she was "pretty upset about her role in the administration, about her superiors, about the President".More news: Andy Serkis To Buttle Up A Storm In Matt Reeves' THE BATMAN
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Volker testified, Vice President Biden wasn't corrupt, that the Ukrainians who worked with him and Hunter Biden were.
The release comes as two White House officials - Wells Griffith, senior director for global energy and environment at the National Security Council, and Michael Duffey, Office of Management and Budget associate director for national security programs - failed to appear for scheduled depositions Tuesday.
In the transcripts and accompanying cache of text messages, US diplomats are shown trying to navigate the demands of Trump and his personal lawyer, Rudy Giuliani, who they soon learn is running a back-channel USA foreign policy on Ukraine.
Before becoming acting chief of staff, Mulvaney ran the White House Office of Management and Budget, which made the decision to block almost $400 million in security assistance for Ukraine last summer. "I told Yermak my assumption", said Meadows, who sits on the House Oversight and Reform Committee.
"He also admits he doesn't know if the aid was held up, or why it was held up, and he still doesn't know", Conway said. "I don't want to spend any time with that".
Meanwhile, investigators said they wanted to hear on November 8 from Trump's acting chief of staff, Mick Mulvaney.
The White House has yet to respond to DailyMail.com's request for comment.
The White House said Mulvaney did not intend to comply with the request. Mulvaney is not expected to appear. "I don't think there's any question it would not lead to a removal", he said.
Pompeo was also not in a photo proudly released by Trump of the raid that killed the Islamic State group's leader Abu Bakr al-Baghdadi, instead attending the wedding of his son's friend in Kansas.
Sondland admitted to impeachment investigators that he understood the linkage was "improper".