WASHINGTON – Marie Yovanovitch, the former U.S. ambassador to Ukraine, said the State Department removed her from the diplomatic post earlier this year after being pressured by President Donald Trump, according to her opening statement in a closed-door hearing on Capitol Hill with lawmakers Friday.

In her remarks, Yovanovitch said she was told by a high-ranking agency official "that the President had lost confidence in me and no longer wished me to serve as his ambassador."

The State Department official "added that there had been a concerted campaign against me, and that the department had been under pressure from the president to remove me since the Summer of 2018," according to her statement. "He also said that I had done nothing wrong and that this was not like other situations where he had recalled ambassadors for cause. I departed Ukraine for good this past May."

During a marathon session that last nearly 10 hours,lawmakers questioned Yovanovitch, a key player in the House impeachment probe, on what she knew about efforts by Trump and his personal attorney, Rudy Giuliani, to push Ukraine to investigate former Vice President Joe Biden, a leading 2020 Democratic presidential candidate.

When it was over, lawmakers declined to discuss any of the specific testimony she offered.

“We are deeply grateful for her decades of service to the country,” said House Intelligence Committee Chair Adam Schiff, D-Calif., who led the hearing. "I think she has been a model diplomat and deserved better than the shabby treatment she received from this president and the Secretary of State.”

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Republicans who attended denounced the impeachment process.

“For goodness sake, now we've got almost 20 hours of testimony from two ambassadors and the American people don't know what happened in those closed-door sessions, other than what the majority has selectively and cherry picked and leaked out,” Rep. Jim Jordan, R-Ohio, the top Republican on the Oversight and Reform Committee.

Jordan and a group of some of the president’s most vocal defenders demanded that House Speaker Nancy Pelosi call for a full House vote on the impeachment inquiry, saying they believed the process was illegitimate.

“Put your money where your mouth is,” Rep. Lee Zeldin, R-N.Y. said in reference to Pelosi. “Create a process, have a vote, let us know where you stand and let's follow rules.”

Pelosi launched the impeachment inquiry last month after the White House released the details of a July 25 phone conversation Trump had with Ukrainian President Volodymyr Zelensky. The inquiry is looking into Trump's efforts to pressure Zelensky to investigate Biden and his son, Hunter.

Yovanovitch, 60, is one of five State Department officials who Democrats have called to Capitol Hill for depositions as they investigate allegations that Trump used the power of his office to solicit foreign interference in the 2020 presidential election.

House Democrats leading the inquiry said the administration tried to keep Yovanovitch silent.

The State Department, at the direction of the White House, directed the ambassador not to appear for her interview Friday, according to a statement from Schiff, Oversight and Reform Committee Chairman Elijah Cummings, D-Md., and Foreign Affairs Committee Chairman Rep. Eliot L. Engel, D-N.Y.

In response, the House Intelligence Committee issued a subpoena to compel her testimony this morning, according to the statement.

"This is the latest example of the Administration’s efforts to conceal the facts from the American people and obstruct our lawful and constitutionally-authorized impeachment inquiry," the statement said. “Any efforts by Trump Administration officials to prevent witness cooperation with the Committees will be deemed obstruction of a co-equal branch of government and an adverse inference may be drawn against the President on the underlying allegations of corruption and coverup.”

Neither the White House nor the State Department responded immediately to a request for comment Friday afternoon.

But Trump, who once described Yovanovitch as "bad news," appeared irritated Thursday about the number of witnesses the House committees are trying to summon.

"How many people can they talk to?," the president said. "We had a simple conversation (with Zelensky). Everybody knows what the conversation was because I gave it immediately when I heard about it ... I don't know why they'd be calling all these people. It's a very bad situation for our country."

Lawmakers filtered in and out of the basement hearing room, which was behind two oak doors with red warning signs reading, “Restricted Area,” but most declined to answer questions about the contents of Yovanovitch’s testimony.

One of the few who did was Rep. Stacey Plaskett, D-Virgin Islands, a member of House Oversight and Reform Committee, who said during a lunch break that Yovanovitch seems like a "very credible witness."

On Thursday, federal prosecutors revealed a plot by two Ukrainian-born business partners to enlist the help of a GOP congressman for the purpose of pressuring the Trump administration to remove Yovanovitch from her post as ambassador to Ukraine.

Yovanovitch remains a State Department employee but is temporarily serving as a fellow at Georgetown University in Washington.

She said in her prepared remarks that while she understands she serves at the pleasure of the president, she was "incredulous that the U.S. government chose to remove an ambassador based, as best as I can tell, on unfounded and false claims by people with clearly questionable motives."

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"To make matters worse, all of this occurred during an especially challenging time in bilateral relations with a newly elected Ukrainian president," according to her remarks. "This was precisely the time when continuity in the Embassy in Ukraine was most needed."

Yovanovitch's decision to testify comes on the same day that another key witness plans to come forward.

Days after being blocked by the Trump administration from testifying before congressional committees, U.S. Ambassador to the European Union Gordon Sondland says that he will testify.

In a statement sent through his attorneys, Sondland said he "looks forward to testifying on Thursday."

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"Notwithstanding the State Department’s current direction to not testify, Ambassador Sondland will honor the Committees’ subpoena, and he looks forward to testifying on Thursday," wrote his attorneys. "Ambassador Sondland has at all times acted with integrity and in the interests of the United States. He has no agenda apart from answering the Committees’ questions fully and truthfully."

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