US President Donald Trump has said he will slap a 35% tariff on Canadian goods starting 1 August, even as the two countries are days away from a self-imposed deadline to reach a new deal on trade, BBC reported.

The missive came as Trump also threatened blanket tariffs of 15% or 20% on most trade partners, and said he would soon notify the European Union of a new tariff rate on its goods.

Trump announced the latest levies on Canada on Thursday in a letter posted to social media and addressed to Prime Minister Mark Carney. 

The US has already imposed a blanket 25% tariff on some Canadian goods, and the country is feeling the pain of the Trump administration's global steel, aluminium and auto tariffs, according to BBC.