White House chief strategist Steve Bannon is the latest top aide of President Donald Trump to leave his post.
Press Secretary Sarah Huckabee Sanders confirmed that Friday was his last day.
His exit follows a review of his position by White House Chief of Staff John Kelly.
Mr Bannon, a right-wing nationalist and former head of Breitbart.com, helped shape the “America First” message of Mr Trump’s election campaign.
But critics had accused him of harbouring anti-Semitic and white nationalist sentiments.
Mr Bannon had competed for influence in the West Wing against rival advisers and the Trump family, according to US media.
Mr Trump fuelled speculation when asked last week about Mr Bannon’s future as he replied: “We’ll see.”
Mr Bannon’s interview this week with the American Prospect magazine reportedly infuriated the president.
The White House aide was quoted as claiming he had the power to fire officials at the State Department and contradicting Mr Trump on North Korea.
Ms Huckabee Sanders’ statement said: “White House Chief of Staff John Kelly and Steve Bannon have mutually agreed today would be Steve’s last day.
“We are grateful for his service and wish him the best.”