OTTAWA - Canada will impose retaliatory tariffs on up to 16.6 billion Canadian dollars (12.8 billion US dollars) worth of US steel, aluminum and other products, Canadian Foreign Minister Chrystia Freeland said on Thursday.

She and Prime Minister Justin Trudeau made the announcement at a press conference hours after US Commerce Secretary Wilbur Ross announced that US tariffs on steel and aluminum imports from the European Union, Canada and Mexico will take effect from Friday.

US President Donald Trump has decided not to extend the temporary steel and aluminum tariff exemptions for these three key trading partners, Ross told reporters at a conference call.

Trudeau called Trump's decision to place tariffs on Canadian aluminum and steel "totally unacceptable."