Speaking in the White House Rose Garden on Wednesday, Trump said “we’re going to be charging a discounted reciprocal tariff of 34 per cent”.

Trump held up a chart listing numerous US trading partners and the tariffs he said they charged the US. The tariffs, which reflect a 10 per cent universal baseline plus 24 per cent specific to China, would take effect on Thursday.

The calculations, he said, reflected “a combined rate of all their tariffs, non monetary barriers and other forms of cheating”, explaining that the US would charge other countries about half as much as they charged the US.

China, he said, charged tariffs of 67 per cent to the US, noting that the figure included the effects of currency manipulation and trade barriers.

Trump had vowed for months to impose reciprocal tariffs to match other countries’ higher tariff rates for specific goods and offset non-tariff barriers that put US exports at a disadvantage.

The new levies, he said, would correct years of “unfair” trade during which other countries had been “ripping” off the US.