"Steve is a valued part of our legacy, and we will always be grateful for his contributions, and what he has helped us to accomplish," Breitbart chief executive Larry Solov said in a statement.
"I'm proud of what the Breitbart team has accomplished in so short a period of time in building out a world-class news platform," Bannon said in a statement.
The Times reports that Bannon's departure comes at the insistence of a onetime financial patron, Rebekah Mercer, following the controversial new book by Michael Wolff, Fire and Fury: Inside the Trump White House. In the book, Bannon was quoted as calling President Trump's son, Donald Trump Jr., "treasonous" and "unpatriotic" for agreeing to meet with Russians, and Trump's daughter Ivanka "dumb as a brick."
Bannon attempted to backtrack his unfiltered rants with an apology, which the White House rejected.
"I don't think there is any way back for Mr. Bannon at this point," White House spokesman Hogan Gidley said. "When you go after somebody's family in the [manner] which he did, two of the president's children are serving this nation, sacrificing in their service, it is repugnant, it is grotesque and I challenge anybody to go and talk about somebody's family and see if that person doesn't come back and comes back hard."
"Steve Bannon has nothing to do with me or my presidency," Trump wrote in a statement following Fire and Fury. "When he was fired, he not only lost his job, he lost his mind."