Donald Trump’s economic adviser has quit his role in the White House over the president’s trade tariffs.

Gary Cohn, viewed as a voice for Wall Street, resigned after battling with the president over his plans to impose hefty steel and aluminium import tariffs.

The 57-year-old, who was a key architect in Mr Trump’s tax reforms, is expected to finalise his exit over the next three weeks.

Mr Trump tweeted: Will be making a decision soon on the appointment of new Chief Economic Advisor. Many people wanting the job – will choose wisely!

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Mr Trump has pushed on with his plans for a 25% tariff on steel imports and a 10% levy on aluminium despite apparent internal White House wrangling over the strategy, and pleas from UK Prime Minister Theresa May.

Jean-Claude Juncker also responded to the plans for tariffs by announcing the EU could tax US bourbon, Levi’s and Harley-Davidsons.

The resignation is another blow to the Trump administration, where the economy is growing but the markets are volatile.

In a statement, Mr Cohn said: 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.

I am grateful to the president for giving me this opportunity and wish him and the administration great success in the future.

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He did not attend a press conference with Mr Trump, despite a seat being marked for him.

When asked about the high turnover rate in the White House, Mr Trump said: Many, many people want every single job… I could take any position in the White House and I’ll have a choice of the 10 top people having to do with that position. Everybody wants to be there.

The top contenders for the job are Peter Navarro, a White House adviser, and conservative commentator Larry Kudlow.

The US dollar fell and stock futures dropped by 1% after the news of Democrat Mr Cohn’s departure.

Paul Mortimer-Lee, chief market economist at BNP Paribas corporate and investment banking said: One of the adults in the room has left. The markets will worry that this is a signal that we will definitely go ahead with these tariffs.

Mr Cohn’s relationship with the president is understood to have soured after Mr Trump’s response to the neo-Nazi clashes in West Virginia in August last year.

(c) Sky News 2018: Economic adviser quits White House over trade tariffs