“You think I’m supposed to be happy with him?” the president said. “I’m not.”

President Donald Trump on Friday did not deny reports that his White House planned to force out a National Security Council expert who testified in the House impeachment inquiry last year.

“Well, I’m not happy with him,” Trump said when asked by a reporter if he wanted the Ukraine expert, U.S. Army Lt. Col. Alexander 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.

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

The Washington Post reported late Thursday that 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 trial by thanking supporters and attacking 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’ Elizabeth McLaughlin contributed reporting to this article.