In the post-impeachment reverberations, an Army officer and Washington's top envoy to the European Union (EU) who testified against US President Donald Trump, have been removed from their positions.
In developments following his acquittal by the Senate, Trump on Friday demanded that the House of Representatives expunge his impeachment because it was a "total political hoax".
Lt. Col. Alexander Vindman, who was a Ukraine expert on the National Security Council (NSC), was escorted out of the White House on Friday. An Army spokesperson said he was being transferred.
Gordon Sondland, the Ambassador to the EU, said he was told that Trump "intends to recall me effective immediately". That would amount to a dismissal.
Earlier, Republican senators started the process of investigating the son of former Vice President Joe Biden, Hunter, whose dealings in Ukraine were behind the impeachment.
And preparing for a second round, House of Representatives Judiciary Committee Chair Jerry Nadler has said that former National Security Adviser John Bolton is likely to be called to testify.
An Army spokesperson said that Vindman and his twin brother, Yevegny Vindman, who was also with the NSC, have "been reassigned to the Department of the Army".
Trump told reporters earlier that he was "not happy" with what Alexander Vindman did.
Alexander Vindman was hailed at the Democratic presidential debate as a hero for daring to defy Trump and testify.
At Joe Biden's request, the audience gave Vindman a standing ovation.
While Alexander Vindman is a wounded veteran of the Iraq War, his brother, also a lieutenant colonel, is an Army lawyer.
The twins' assignments to the White House was to end in July, but they will continue at their rank in the military on other assignments.
They are refugees from Ukraine when it was a part of the Soviet Union and came to the US when they were children.
Alexander Vindman's lawyer attributed his transfer to Trump's displeasure with his testimony and said, "Vindman was asked to leave for telling the truth".
Alexander Vindman had testified during the House of Representatives impeachment inquiry that he was one of the NSC officials listening on the July 25, 2019 phone call between Trump the Ukrainian President Volodymyr Zelensky during which Trump asked him to investigate the Bidens.
He said that he was concerned about Trump's request and reported it to a senior White House lawyer.
Senate Democrat Leader Chuck Schumer said the action "went too far" and exposed Trump's "weakness".
Sondland is a hotelier with no foreign policy experience who donated a million dollars to Trump's inauguration celebrations.
He testified that he thought there was a "quid pro quo" and Trump withheld military aid to Ukraine to pressure Zelentsky to announce a probe of the Bidens.
While his father was in charge of relations with Ukraine, Hunter Biden was appointed a director of a Ukrainian gas company with monthly payments of at least $50,000 even though he had no experience in the area and had been to leave the Navy amid allegations of drug use.
Joe Biden later said that he had the prosecutor looking into the gas company, Burisma, dismissed.
A possible fallout of the impeachment that brought attention to the Bidens' dealings is the tanking of Joe Biden in the Democratic Party process of selecting its candidate to run against Trump.
He came in fourth in Iowa, which held the party election on Monday, and, according to polls, is also trailing in New Hampshire where primaries are to be held next week.
Chairs of the Senate Finance Committee, Chuck Grassley, and Homeland Security Committee, Ron Johnson, confirmed there was an investigation afoot on Friday when they accused Democrats of leaking information about it.
The Treasury Department had reportedly complied with the Senate request for records relating to Hunter Biden and the Secret Service had been asked for reports of his travels to Ukraine and China when he was under the agency's protection as the son of a vice president.
He also served as a director of a Chinese company while his father was criticising Trump's trade war with Beijing.
Bolton has written in the manuscript for an as yet unpublished book that Trump had linked withholding of about $400 million to Ukraine to the request for the Biden inquiries.