Trump announced the Vietnam deal on Wednesday, saying that the US would place a 20 per cent tariff on Vietnamese exports to the US and a 40 per cent rate on goods deemed transshipped through the nation — a reference to the practice whereby components from China and possibly other nations are routed through third countries on their way to the US.

Trump told reporters he would begin sending countries letters setting tariff rates rather than negotiate 170 trade deals worldwide.

The US government is to start sending out letters to countries with details of higher US tariff rates that will begin on 1 August, President Donald Trump has said. Between 10 to 12 letters will go out on Friday,