TORONTO — Roughly $900 billion in annual trade between Canada and the United States — and with it, traditionally chummy bilateral ties — is on the brink of upheaval, with President Donald Trump threatening to impose sweeping tariffs on Canada as early as this weekend.

Upon returning to office, U.S. President Donald Trump has launched numerous tariff threats. They range from broad ones - a universal tariff on foreign-imported goods - to ones aimed at specific sectors,

The U.S. is threatening a two-stage tariff plan in which Canada and Mexico could get hit with initial trade penalties within days then face broader penalties this spring.

Canada's top politicians are pushing to convince U.S. President Donald Trump to back off his tariff threat. David Akin looks at how Foreign Affairs Minister Mélanie Joly is making her pitch in Washington,