Washington: US President Donald Trump has fired another tariff salvo at northern neighbour Canada, telling Prime Minister Mark Carney he will impose a 35 per cent tax on all Canadian imports from August 1.

Steel and aluminium, which figure prominently among those imports, will continue to be levied at 50 per cent, and all other sectoral tariffs remain the same.

Canadian Prime Minister Mark Carney with Donald Trump at the G7 summit in June.Credit: AP

The announcement came in a letter to Carney published by Trump on social media – one of two dozen letters the US president has signed and made public this week as he increases pressure on trading partners before the new August deadline.

“If for any reason you decide to raise your tariffs, then, whatever the number you choose to raise them by, will be added onto the 35 per cent that we charge,” he warned.

Trump reiterated his frustration about the drug fentanyl being trafficked over the Canadian border, even though it accounts for less than 1 per cent of fentanyl arriving in the US, according to most estimates.

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