More than a dozen nations with the highest trade deficits, including Syria (41 per cent) and Switzerland (39 per cent), will face tariffs exceeding 15 per cent.
The tariff on Canadian goods increased from 25 per cent to 35 per cent, with the White House citing Canada's "continued inaction and retaliation."
The new policy, initially set for 1 August, has been delayed until 7 August to allow US Customs and Border Protection time to implement the changes.