WASHINGTON (Reuters) - Two U.S. diplomats told lawmakers the State Department was being used for domestic political purposes under President Donald Trump and warned that would hurt American interests, according to transcripts released on Monday in Congress’ impeachment investigation.

The transcripts were the first released from the closed-door inquiry by the House Foreign Affairs, Intelligence and Oversight panels. They painted a detailed picture of the distress felt by top U.S. diplomats as Trump allies tried to pressure Ukraine to launch investigations into the Republican president’s domestic political rivals.

Marie Yovanovitch, whom Trump abruptly recalled as ambassador to Ukraine in May, told U.S. House of Representatives committees about the attacks against her in conservative media and from close allies of Trump, questioning her loyalty to the president.

“I was shocked,” she said of learning from Assistant Secretary of State Philip Reeker that Trump had wanted her to leave her post for months.

Rudy Giuliani, the president’s private attorney, and Donald Trump Jr., the president’s son, had also posted criticism of her on social media.

“If you have the president’s son saying, you know, we need to pull these clowns, or however he referred to me, it makes it hard to be a credible ambassador in a country,” she said.

Yovanovitch said she first learned in late 2018 that Giuliani had been involved in Ukraine policy when Ukrainian officials alerted her to the former New York mayor’s communications with a former Ukrainian prosecutor general.

She described how Gordon Sondland, the U.S. ambassador to the European Union, had urged her to use Twitter to express support for Trump in order to save her job. “He said, you know, you need to go big or go home. You need to, you know, tweet out there that you support the president,” she said.

Several witnesses have said Sondland, a major Trump donor, played a major role in Ukraine policy, despite the country not being part of the European Union. Sondland also testified in the House probe, and his transcript is expected on Tuesday.

Michael McKinley, a former top adviser to Secretary of State Mike Pompeo, told House investigators that he quit his post after the State Department opted not to defend Yovanovitch from criticism by Trump and his political allies.

He also cited his concern over “what appears to be the utilization of our ambassadors overseas to advance domestic political objectives,” McKinley told lawmakers.

“I feel that this is not the way we maintain the integrity of the work we do beyond our borders. We’re meant to project nonpartisanship overseas,” he said.

The Democratic-led House investigation is focused on a July 25 phone call in which Trump asked Ukrainian President Volodymyr Zelenskiy to investigate former Vice President Joe Biden, a leading Democratic rival as Trump seeks re-election in November 2020.

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The committees began releasing interview transcripts as they prepare for public hearings that could start this month.

Republicans have complained that the inquiry is insufficiently transparent. Democrats say they are following House rules on investigations and that previous impeachment investigations have had both closed-door and public testimony.

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FELT THREATENED

Yovanovitch testified on Oct. 11 that she felt threatened by Trump telling Zelenskiy on the call that she was going to “go through some things.”

“I didn’t know what it meant. I was very concerned,” she said. “I still am.”

She said she was astonished to be featured in a presidential phone call and that Trump would speak about her “or any ambassador in that way to a foreign counterpart.”

Trump has denied wrongdoing and accused Democrats of unfairly targeting him to reverse his surprise election victory in 2016.

Four U.S. officials called to testify by Democrats did not show up as requested on Monday, lawmakers said, and the president pressed his demand for a whistleblower to appear.

Some Democrats say Trump, who has ordered administration officials not to cooperate with the impeachment inquiry, should face an obstruction of Congress charge among the counts they plan to consider.

The testimony of the four witnesses - from the White House budget office and National Security Council - would have been important to determining whether Trump used foreign aid to Ukraine as leverage to secure a political favor.

Lawmakers were especially interested in questioning the lawyer, John Eisenberg, who took the unusual step of moving a transcript of the call into the White House’s most classified computer system, according to a person familiar with last week’s testimony by Army Lieutenant Colonel Alexander Vindman, an NSC official who listened in on the call.

The committees have asked Vice President Mike Pence’s special adviser for Russia and Europe, Jennifer Williams, to testify on Thursday in closed session, an official working on the inquiry said. Pence’s office did not immediately answer a query on whether Williams would appear.

“There is no reason to call witnesses to analyze my words and meaning,” Trump tweeted on Monday.

If the House votes to approve articles of impeachment, the Republican-controlled Senate would then hold a trial on whether to remove the president from office.