Canada is the second-largest trading partner of the US after Mexico. Its exports are less diversified than those of the US.

In recent months, business owners on both sides of the border have expressed fears over the trade war's fallout. Many expect prices of goods to rise and the number of customers to fall.

Last month, the White House imposed 50% tariffs on around $20bn (£14.8bn) of Canadian goods after several rounds of talks had broken down.

Those tariffs hit sectors including Canada's furniture and wine industries, as well as some sporting and fishing equipment businesses.

Canada responded with what Carney called "dollar-for-dollar" tariffs on US goods like steel, clothing and furniture. The counter-duties came into effect after midnight on Tuesday.

Canada is "discriminating" against US businesses by restricting American goods while not doing the same to the same products from other countries, the White House said when announcing the new import restrictions on Tuesday.

Some products, like whey and non-alcoholic beer, have been banned from import entirely, while tariffs have been further hiked for others, including for cheeses and cheese substitutes - which were not covered by bans - and for motorboats.

The list of Canadian products banned by the White House include:

Those facing higher import taxes include:

Washington has targeted "significant industries" for Canada, including its politically influential dairy businesses, said economics lecturer Scott French from the University of New South Wales in Australia.

Trump has previously argued that Canada's system - which has production quotas, set pricing, and import limits on dairy, eggs, and poultry - is unreasonable to US farmers.

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