Gordon Sondland, the U.S. ambassador to the European Union, revised his initial testimony significantly, amending it to say he told a top Ukrainian official that the country would “likely” not receive military aid unless it announced investigations into President Donald Trump’s political rivals, according to a transcript released Tuesday by the committees conducting the impeachment inquiry.

In an amendment to his transcribed testimony, Sondland said his recollections were “refreshed” after reviewing opening statements from diplomats William Taylor and Tim Morrison.

The House Democratic chairs leading the impeachment inquiry released transcripts Tuesday from Sondland and Kurt Volker, the former special envoy to Ukraine.

And House investigators on Tuesday summoned acting White House Chief of Staff Mick Mulvaney to testify on what he knows about the withheld aid package to Ukraine at the heart of the impeachment inquiry.

Democrats indicated that Sondland’s initial testimony was at odds with other current and former Trump officials who testified about the president’s interactions with Ukraine.

In his original deposition in October, Sondland largely defended Trump against allegations of wrongdoing, saying he recalled “no discussions” mentioning potential 2020 Democratic presidential nominee Joe Biden and his son Hunter Biden. It was not until much later that he realized there was a connection between Burisma and the Bidens, he said.

At least two other witnesses, including Taylor, the acting ambassador to Ukraine, disputed that point. Many current and former Trump officials who’ve given impeachment depositions have named Sondland and Volker as administration enablers and foot soldiers of Trump’s personal lawyer Rudy Giuliani, who was pushing a parallel foreign policy to pressure Ukraine to investigate Trump’s domestic political rivals and promoting a conspiracy theory that Democrats colluded with Ukraine in the 2016 election.

The impeachment panel on Monday released transcripts of testimony from former U.S. Ambassador to Ukraine Marie Yovanovitch and former senior State Department adviser Michael McKinley, signaling that a pivot to the public phase of the impeachment process is underway.

The Yovanovitch transcript outlined her concerns about Giuliani’s outsize influence on the administration’s Ukraine policy and his efforts to have her removed from her post. McKinley left the State Department earlier this year over “what appears to be the utilization of our ambassadors overseas to advance domestic political objectives,” he told lawmakers.

Meanwhile, White House officials Wells Griffith and Michael Duffey did not show up for their scheduled depositions Tuesday. Four administration officials declined to appear for their scheduled depositions a day earlier.

John Bolton, former national security adviser who left the White House in September over policy differences with Trump, is scheduled to testify Thursday, though it is also unclear whether he will appear.

Here is the latest on the impeachment investigation:

He’s not here: The official deposition transcript of McKinley released by the Intelligence, Foreign Affairs and Oversight committees lists two members as present who are not on any of the committees — Republican Reps. Rob Bishop of Utah and Markwayne Mullin of Oklahoma. Bishop’s office did not return a request for comment. Mullin’s spokeswoman said he was not present for the McKinley deposition and shared a letter with Roll Call that Mullin sent to Intelligence Chairman Adam B. Schiff Tuesday asking his name be removed from the record.

“Manipulated narrative”: House Freedom Caucus Chairman Andy Biggs issued a statement Tuesday evening accusing Democrats of trying to control the narrative on impeachment by releasing select portions of deposition transcripts to major media outlets ahead of the full public release. The Arizona Republican accused Democrats of “knowing that they were about to release the Sondland and Volker transcripts” and leaking a “manipulated narrative” to outlets including the New York Times. “The transcripts themselves are hundreds of pages, ensuring that tonight’s news will likely run with their narrative and message before most people have a chance to fully read,” he said.

Volker’s testimony: In his testimony before the House impeachment inquiry, Volker blamed a senior Ukrainian defense official, Oleksandr Danyliuk, for a bad July 10 meeting at the White House with Bolton, the national security adviser at the time. That meeting is now one of several focal points in the House’s impeachment inquiry.

“He was getting into the weeds about restructuring the intelligence service, the security services in Ukraine, into the weeds about restructuring the Defense Ministry,” Volker said in the transcript of his October deposition released Tuesday. “This is not the level of conversation you should be having with the national security adviser of the United States. You should be conveying a much more top-line strategic message.”

Volker’s pinning the blame on a wonky Ukrainian bureaucrat clashes with testimony provided by Army Lt. Col. Alexander Vindman, the top Ukraine expert on the National Security Council, who testified that the meeting was going well until Sondland brought up certain investigations Trump wanted the Ukrainian government to open into his domestic political rivals. At that point, Bolton cut the meeting short.

An ‘insidious’ continuum: In his deposition unsealed Tuesday, Sondland described a series of demands from Giuliani that “kept getting more insidious” from May to September.

And in four new pages of revised testimony, Sondland appeared to acknowledge that the White House was seeking a quid pro quo of a “public anti-corruption statement” from Ukrainian President Volodymyr Zelenskiy in exchange for unfreezing nearly $400 million in military aid. 

Sondland, an Oregon-based hotelier and major Trump donor who had virtually no foreign policy experience before he became Trump’s ambassador to the EU last July, told lawmakers that he did not become aware “until much later” of Giuliani’s intention to use military aid and a Trump-Zelenskiy White House meeting as leverage to pressure Ukraine to investigate the president’s domestic political rivals.

Sondland’s involvement in the Ukraine affair began, he testified, in an Oval Office meeting on May 23, where Trump repeatedly told him, Volker, and Energy Secretary Rick Perry to “talk to Rudy” about concerns regarding the Eastern European country. The president was unspecific about those concerns. “Ukraine is a problem,” Trump said, according to Sondland.

Giuliani’s demands of Ukrainian officials grew increasingly specific as the Trump administration placed a hold on the military aid in July and continued to withhold it until September. The White House simultaneously delayed committing to Zelenskiy’s requested White House meeting with Trump until he had acquiesced to Giuliani’s demands.

At first, Sondland was asked to “get the Ukrainians to give a statement about corruption,” he said.

Then he was told, “No, corruption isn’t enough, we need to talk about the 2016 election and the Burisma investigations,” he testified. “And it was always described to me as ongoing investigations that had been stopped by the previous administration and they wanted them started up again,” Sondland told lawmakers.

Sondland and others negotiated for “many weeks” with the Ukrainians on a press statement where Zelenskiy would announce he was opening probes into the Bidens, Burisma and Giuliani’s 2016 election interference conspiracy theory, he said.

In a Sept. 1 conversation in Warsaw with top Zelenskiy adviser Andriy Yermak, Sondland told Yermak that “the resumption of U.S. aid would likely not occur until Ukraine provided the public anti-corruption statement that we had been discussing for many weeks,” according to his revised testimony. Sondland later learned, though he does not remember how, that Giuliani and Trump wanted Zelenskiy himself to publicly announce the probes.

Zelenskiy never delivered such a statement.

Around that time, Sondland finally “made the Biden-Burisma connection” and “became aware that there might be a link between the White House visit and aid to the Ukraine that was being held up” and efforts to get Ukraine to announce Giuliani’s requested investigations, Sondland said.

But at that point the Trump administration was under pressure to unfreeze the military aid to Ukraine after multiple media outlets reported the holdup.

“The aid was released, and then this whole thing blew up. That’s the best I can recall the sort of progression,” Sondland said.

The Democratic chairs of the three committees conducting the impeachment investigation issued a statement on Tuesday condemning the alleged efforts of Trump and Giuliani to “use the State Department to press Ukraine to announce investigations beneficial to the President’s personal and political interests.”

The Democrats also criticized the State Department for “continuing to obstruct” the impeachment probe by “refusing to provide subpoenaed records,” including text messages Sondland has handed over to the department.

‘Three Amigos’: Sondland and Volker worked closely with Giuliani from within the administration to push for Ukraine to investigate theories about the Bidens and widely debunked theories about Ukrainian interference in the 2016 U.S. presidential election, according to reports of impeachment witness testimony.

Along with Perry, Sondland and Volker were known among other diplomatic officials as Trump’s “Three Amigos,” running a parallel foreign policy in Ukraine directed largely by Giuliani.

Sondland was warned by multiple national security officials that his repeated comments at a July 10 meeting with Ukrainian officials stressing the importance of the proposed investigations were inappropriate.

“I stated to Ambassador 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,” Vindman, the NSC Ukraine expert, said in his opening statement last week.

Volker told lawmakers in his deposition that he was aware Giuliani’s involvement in U.S.-Ukrainian foreign policy was fueling a divide between the two countries, whose strategic partnership is widely seen as a key buffer separating Russia from the rest of mainland Europe.

“I therefore faced a choice: Do nothing, and allow this situation to fester; or try to fix it. I tried to fix it,” he told lawmakers.

White House response: White House Press Secretary Stephanie Grisham responded to the Tuesday transcript release and defended the president from quid pro quo allegations.

“Both transcripts released today show there is even less evidence for this illegitimate impeachment sham than previously thought,” Grisham said in a statement.

She argued Sondland merely “presumed” — and did not know for a solid fact — there was a link between the withholding of military aid and Zelenskiy announcing anti-corruption probes.

Trump Hotel: House Democratic investigators have not been solely focused on Trump allegedly pressuring Ukraine to investigate a political rival as they’ve questioned witnesses in the impeachment inquiry, a transcript of one of the closed-door depositions revealed.

As the Intelligence, Oversight and Foreign Affairs committees interviewed Volker, a Democratic lawyer asked him why he had met Giuliani and Ukrainian government officials at Trump International Hotel in Washington on multiple occasions.

The question was an apparent effort by Democratic investigators to see whether the Ukrainians were trying to curry favor with the president by staying in the hotel he owns, possibly putting Trump in violation of the Constitution’s emoluments clause.

The emoluments clause prohibits presidents from accepting, without the consent of Congress, “any present, emolument, office, or title, of any kind whatever, from any king, prince, or foreign state.”

Mulvaney summoned: The leaders of the three committees leading the impeachment inquiry sent a letter Tuesday to Mulvaney asking him to appear for a deposition Friday.

Schiff, Foreign Affairs Chairman Eliot L. Engel and acting Oversight Chairwoman Carolyn B. Maloney told the acting White House chief of staff they believe he has “substantial first-hand knowledge and information” relevant to the inquiry based on others’ testimony.

“Specifically, the investigation has revealed that you may have been directly involved in an effort orchestrated by President Trump, his personal agent, Rudolph Giuliani, and others to withhold a coveted White House meeting and nearly $400 million in security assistance in order to pressure Ukrainian President Volodymyr Zelenskiy to pursue investigations that would benefit President Trump’s personal political interests, and jeopardized our national security in attempting to do so,” the three leaders said.

Mulvaney is unlikely to show up for the deposition. He has already ignored a subpoena the committees issued to him on Oct. 4 for documents.

‘A lot of explaining to do’: House Oversight member Mark Meadows, a North Carolina Republican, told reporters Tuesday that what he’s taken away from all the witness testimony is that there is no evidence that U.S. aid to Ukraine was withheld to force a politically charged investigation.

“That connection is just not there,” he said.

Meadows, the former chairman of the hard-line conservative Freedom Caucus, said knowing the identity of the whistleblower “would be helpful in terms of motivations and coordination.”

He said he does not know the whistleblower’s identity but said if reports about the person and his or her connection to the Democrats and coordination with the Intelligence Committee are true, then “Chairman Schiff has a lot of explaining to do.”

“Many of us see that as grossly unfair. If that happened, we need to know about it,” Meadows said of the alleged coordination, which Schiff has denied.

Another investigation: Key Senate Democrats on Tuesday continued to push the Department of Defense’s acting inspector general to open an investigation into the White House’s decision to temporarily withhold the aid to Ukraine.

The senators, all of whom sit on the Appropriations Committee, requested the IG open an investigation in a September letter. They were updated this week on Glenn Fine’s consideration of that request, according to their letter.

“We recognize that these are difficult, high profile, and potentially time-consuming issues,” Sens. Tammy Baldwin, Richard J. Durbin, Dianne Feinstein, Patrick J. Leahy, Patty MurrayJack Reed and Tom Udall wrote. “But we remain confident that you will pursue them with the same seriousness you have demonstrated with previous investigations.”

Exceeding authority: The Justice Department’s Office of Legal Counsel argued in a memo that congressional committees cannot compel executive branch witnesses to testify about matters that are potentially protected by executive privilege without the assistance of agency counsel.

“Because the committee may not bar agency counsel from assisting an executive branch witness without contravening the legitimate prerogatives of the Executive Branch, a HPSCI subpoena requiring such a result would exceed the committee’s lawful authority and thus could not be enforced,” the OLC memo said.

House depositions rules actually bar witnesses from being accompanied by anyone other than personal counsel.

Defying subpoenas: House Oversight Democrat Jamie Raskin told reporters Tuesday morning that neither of the scheduled deposition witnesses — Griffith and Duffey — showed up to testify and that they appeared unlikely to do so.

Correction 12:52 p.m. | An earlier version of this story misidentified the day Mulvaney had been summoned to testify.