President Donald Trump's top economic adviser Gary Cohn is resigning, a move that would leave a troika of trade hawks running the United States' trade policy.
Mr Cohn, the National Economic Council director, announced the decision on Tuesday, as he seemed poised to lose an internal struggle over Mr Trump's plan to impose a 25 per cent tariff on steel imports and 10 per cent on aluminium imports.
"It has been an honour to serve my country and enact pro-growth economic policies to benefit the American people, in particular the passage of historic tax reform," Mr Cohn said in a statement.
The White House downplayed the idea that Mr Cohn, 57, resigned over more aggressive trade policies.
The supporter of the classic pro-business Republican agenda - deregulation and tax cuts - had reportedly fought hard to head off the proposed tariffs.
His departure is seen as a victory for the three trade hawks advising the President.
Most prominent is Dr Peter Navarro, who has been fielded on cable talk shows to defend the tariff decision. The others are Commerce Secretary Wilbur Ross and US Trade Representative Robert Lighthizer.
NO CHAOS, ONLY ENERGY
The new Fake News narrative is that there is CHAOS in the White House. Wrong! People will always come & go, and I want strong dialogue before making a final decision. I still have some people that I want to change (always seeking perfection).
There is no Chaos, only great Energy!
U.S. PRESIDENT DONALD TRUMP, in a Twitter post on Tuesday, pushing back against reports that his White House is in chaos, following the resignation of senior staff members.
Dr Navarro, the director of the White House's Trade and Manufacturing Policy office, is a former professor of economics.
He made waves in 2012 with a book and film titled Death By China. The book features an image showing a dagger plunged bloodily into the heart of a map of the US.
In a July 2016 column in the Los Angeles Times, Dr Navarro wrote: "China has been waging an undeclared trade war on the US since joining the World Trade Organisation (WTO) in 2001.
"The casualties are obvious: More than 50,000 American factories shuttered. For Trump, steep tariffs are a strategic negotiating strategy to stop China, or any other country, from cheating on international trade deals."
Mr Ross, while a Sinophile, shares Dr Navarro's views. In late 2016, he and Dr Navarro co-authored a paper in which they referred to "self-inflicted negative impact from poorly negotiated trade deals and the failure to enforce them".
"These bad deals include most notably Nafta… and China's entry into the (WTO)... a critical catalyst for America's slow growth plunge," they wrote, referring to the North American Free Trade Agreement.
Mr Lighthizer is a veteran of the anti-Japan trade measures of the 1981-1989 Reagan administration which, among other things, slapped a quota on Japanese cars.
On Monday in Mexico City, Mr Lighthizer told reporters the US was prepared to break Nafta up into separate agreements if it could not meet its priorities.
"The economic nationalists now certainly have the upper hand and their camp is bigger. I think they are going to be very influential in the administration," Ms Monica de Bolle, a senior fellow at the Peterson Institute for International Economics, was quoted as saying by Reuters.
Analysts who followed Mr Trump's 2016 campaign said the developments are not surprising.
"The President ran on a platform that was the most protectionist of any candidate since 1932," Dr T. J. Pempel, a professor of political science, said on Tuesday.
Mr Cohn is the latest in a series of high-profile departures from the White House, including communications director Hope Hicks.
SEE OPINION: Trump's trade follies presage more protectionism