Andrew McCabe is describing his firing as part of President Donald Trump's "ongoing war" with the FBI and the special counsel investigation.
"This attack on my credibility is one part of a larger effort not just to slander me personally, but to taint the FBI, law enforcement and intelligence professionals more generally," McCabe said in a statement after his firing.
"It is part of this administration's ongoing war on the FBI and the efforts of the special counsel investigation, which continue to this day. Their persistence in this campaign only highlights the importance of the Special Counsel's work," he added.
Trump had regularly taunted McCabe over accusations he misled internal investigators at the Justice Department.
His fall follows an internal review by Justice Department Inspector General Michael Horowitz. While details of the review have not been publicly released, it is said to conclude McCabe misled investigators about his role in directing other officials at the FBI to speak about his involvement in a public corruption investigation into the Clinton Foundation, according to a source briefed on it.
Horowitz's report findings were referred to the FBI's Office of Professional Responsibility, who recommended McCabe's termination. In a last-ditch effort Thursday to avoid the firing, McCabe and his lawyer met officials at the Justice Department for several hours.
"I absolutely never misled the inspector general in any way," McCabe told CNN, calling his highly public downfall the result of "a series of attacks designed to undermine my credibility and my reputation."
'Great day for democracy'
McCabe was expected to retire on his 50th birthday Sunday, when he would have become eligible for early retirement benefits. His termination could affect a portion of his anticipated pension.
Shortly after the announcement, Trump described it as "a great day for democracy."
Andrew McCabe FIRED, a great day for the hard working men and women of the FBI - A great day for Democracy. Sanctimonious James Comey was his boss and made McCabe look like a choirboy. He knew all about the lies and corruption going on at the highest levels of the FBI!
— Donald J. Trump (@realDonaldTrump) March 17, 2018