Emboldened Trump fires 2 officials who testified in impeachment inquiry An ambassador and a White House expert were removed from their posts.

President Donald Trump on Friday fired a U.S. ambassador and a White House national security aide, both of whom testified in the House impeachment inquiry, as the newly emboldened president took retribution on officials he believed wronged him during the impeachment process.

The U.S. ambassador to the European Union, Gordon Sondland, said late Friday Trump had recalled him from his post, just hours after U.S. Army Lt. Col. Alexander Vindman, an expert on Ukraine, was reassigned from his position on the National Security Council.

Both men had testified publicly about the president's attempts to get Ukraine to investigate his political rival, former Vice President Joe Biden. Trump had publicly lashed out against them at the time but had held off removing them until the Senate impeachment trial, when ended in the president's acquittal, came to a close on Wednesday.

Vindman and his twin brother, Yevgeny Vindman, another Army lieutenant colonel who worked at the NSC, were escorted off White House grounds Friday, their lawyer, David Pressman, said.

Yevgeny Vindman, a lawyer who focused on ethics for the NSC and who did not testify in the inquiry, was brought out "suddenly and with no explanation," Pressman said.

Speaker of the House Nancy Pelosi called Vindman an "American patriot" Friday night, saying "history will remember Lt. Col. Vindman as an American hero."

"On the battlefield when he earned a Purple Heart, and in the House trial when he spoke truth to power. His brave testimony showed America that right still matters," Pelosi said. "President Trump is impeached forever. The shameful firing of Col. Vindman was a clear and brazen act of retaliation that showcases the president's fear of the truth. The President's vindictiveness is precisely what led Republican Senators to be accomplices to his cover-up. The firing of this patriotic soldier is a sad and shameless loss for America's security."

While the Vindman brothers were on detail from the Army, Sondland was a Trump megadonor who the president had appointed to represent him in Brussels.

"I was advised today that the President intends to recall me effective immediately as United States Ambassador to the European Union," Sondland said in a statement. "I am grateful to President Trump for having given me the opportunity to serve, to Secretary [of State Mike] Pompeo for his consistent support, and to the exceptional and dedicated professionals at the U.S. Mission to the European Union."

Sondland added, "I am proud of our accomplishments. Our work here has been the highlight of my career."

Sondland told the House Intelligence Committee in November that Trump sought a quid pro quo with Ukraine, carried out by the president's personal lawyer Rudy Giuliani.

An Army spokesperson told ABC News that the Vindman brothers had been reassigned.

"We can confirm that both Lt. Cols. Vindman have been reassigned to the Department of the Army, out of respect for their privacy, we will not be providing any further information at this time," the spokesperson said Friday night.

Earlier in the day, President Donald Trump did not deny reports that his White House planned to force out Vindman.

"Well, I'm not happy with him," Trump said when asked by a reporter if he wanted Vindman out of the White House. "You think I'm supposed to be happy with him? I'm not."

Asked if Vindman was going to leave -- and if he should leave -- Trump responded, "They'll make that decision."

"You'll be hearing," he added.

A day earlier, White House Press Secretary Stephanie Grisham told Fox News that "maybe people should pay" for subjecting the president to the impeachment process.

Vindman's lawyer said it was clear why Vindman was dismissed, two days after the Senate acquitted Trump in his impeachment trial.

"There is no question in the mind of any American why this man's job is over, why this country now has one less soldier serving it at the White House," Pressman said in a statement. "LTC Vindman was asked to leave for telling the truth. His honor, his commitment to right, frightened the powerful.

"The truth has cost LTC Alexander Vindman his job, his career, and his privacy," Pressman added. "He did what any member of our military is charged with doing every day: he followed orders, he obeyed his oath, and he served his country, even when doing so was fraught with danger and personal peril. And for that, the most powerful man in the world - buoyed by the silent, the pliable, and the complicit - has decided to exact revenge. "

The NSC declined to comment on either brother's status. "We do not comment on personnel matters," a spokesman for the NSC, John Ullyot, said.

Trump has previously attacked Vindman, a Purple Heart recipient wounded in Iraq, for his testimony.

The Washington Post reported late Thursday that Trump planned to push out Vindman from his post in retaliation -- as early as Friday. Bloomberg News reported, citing unnamed sources, the White House was "preparing to position the move as part of a broader effort to shrink the foreign policy bureaucracy."

Vindman is an active duty service member serving a term on the NSC.

He raised red flags after listening to Trump's July 25, 2019, phone call with Ukraine's president -- which sparked the House's impeachment inquiry -- and testified before the House Intelligence Committee in November.

During lengthy remarks on Thursday where Trump celebrated his acquittal in a Senate impeachment, he thanked supporters and attacked those he believed had wronged him. The president took a shot at Vindman, noting the lieutenant colonel had raised questions about omissions in a rough transcript of the phone call. He also referred to Vindman's twin brother, Yevgeny, also an Army lieutenant colonel who works on the National Security Council.

Trump has also called Vindman a "never Trumper" -- with no evidence -- and mocked him wearing his Army uniform during his testimony.

Defense Secretary Mark Esper on Friday was asked if he would welcome Vindman back to the Department of Defense and what the Pentagon would do to ensure Vindman did not face retribution by the president or others.

"We welcome back all of our service members wherever they serve to any assignment they're given," Esper replied. "I would refer you to the Army for any more detail on that. And as I said, we protect all of our persons, service members from retribution or anything like that."

ABC News' Katherine Faulders and Elizabeth McLaughlin contributed to this report.