Astrid Riecken For The Washington Post via Getty Images(WASHINGTON) -- The intelligence community watchdog ousted by President Donald Trump says that he believes his firing was related, at least in part, to his handling of the Ukraine whistleblower complaint that set in motion the House of Representatives' impeachment inquiry.

"While I understand that the President can remove Inspectors General for cause, I am disappointed and saddened that President Trump has decided to remove me as the Inspector General of the Intelligence Community because I did not have his 'fullest confidence,'" IC Inspector General Michael Atkinson said in a statement late Sunday. "It is hard not to think that the President's loss of confidence in me derives from my having faithfully discharged by legal obligations as an independent and impartial Inspector General, and from my commitment to continue to do so."

Atkinson further used the statement to express solidarity with government employees who hope to raise alarm about potential wrongdoing they witness, but who may be afraid to do speak out in the current climate.

"It is important to remember, as others have said, that the need for secrecy in the Intelligence Community is not a grant of power, but a grant of trust," Atkinson says. "Please do not allow recent events to silence your voices."

President Trump's late Friday night firing of Atkinson in the midst of a global pandemic has drawn outrage from Democrats and government transparency advocates, who have cast it as an overt act of political retribution intended to intimidate other agency watchdogs.

On Saturday, Trump tore into Atkinson in a briefing with reporters at the White House, repeatedly singling out his decision to alert Congress last year to the existence of the complaint from a member of the intelligence community who believed Trump was abusing his office when he asked Ukrainian President Volodymyr Zelenskiy to investigate former Vice President Joe Biden and his son.

"I thought he did a terrible job, absolutely terrible," Trump said, later calling Atkinson a "disgrace to IGs."

Atkinson split with the Justice Department and then-acting Director of National Intelligence Joseph Maguire in his determination that the whistleblower complaint amounted to an "urgent concern" under the law that required him to disclose its contents to Congress.

"As an Inspector General, I was legally obligated to ensure that whistleblowers had an effective and authorized means to disclose urgent matters involving classified information to the congressional intelligence committees, and that when they did blow the whistle in an authorized manner, their identities would be protected as a guard against reprisals," Atkinson said in the Sunday statement.

But the disclosure drew outrage from President Trump, who sought to cast Atkinson as a member of the 'deep state' resistance looking to remove him from office even though Trump had personally appointed Atkinson to the position.

"He took a whistleblower report which turned out to be a fake report, it was fake, it was totally wrong," Trump said.

The contents of the whistleblower complaint, in fact, have been largely validated through public congressional testimony from senior White House and diplomatic officials in the House inquiry as well as the transcript of the Trump-Zelenskiy call, that resulted in Trump's impeachment and subsequent acquittal in the U.S. Senate.

Atkinson's abrupt firing drew a rare statement from Justice Department Inspector General Michael Horowitz, who on behalf of the Council of the Inspectors General on Integrity and Efficiency defended Atkinson for his "commitment to the rule of law and independent oversight," as well as his handling of the Ukraine whistleblower complaint.

"The Inspector General Community will continue to conduct aggressive, independent oversight of the agencies that we oversee," Horowitz said.

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