However, Trump's threats have changed over time, ranging from small levies to ones exceeding 200%, leaving other nations and businesses unclear of what is to come next. Here is a roundup of Trump's trade-related threats.

The man U.S. President Donald Trump has chosen to oversee his tariff agenda says hitting Canada with 25 per cent across-the-board duties would be an emergency measure to achieve border security — and could be followed by more tariffs in the future.