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.

Any Canadian response to U.S. tariffs will be regionally fair and equitable and not single out Alberta, Canada's main oil-producing province, Canada's Energy and Natural Resources Minister Jonathan Wilkinson said on Wednesday.

If the U.S. follows through on President Donald Trump's threat to impose massive tariffs on Canada as early as Saturday, Ottawa could hit back with retaliatory tariffs within hours or days, according to international trade lawyers.