OTTAWA (Reuters) – Canada will announce on Tuesday that it is going ahead with a threat to slap retaliatory tariffs on U.S. goods after Washington said it would impose punitive measures on Canadian aluminum imports, CTV said on Monday.

Deputy Prime Minister Chrystia Freeland said last month that Ottawa would impose sanctions on C$3.6 billion ($2.7 billion) worth of U.S. aluminum and products containing aluminum. The measures would come into force by Sept 16, she added.

Canada promised to retaliate after U.S. President Donald Trump moved in August to reimpose 10% tariffs on some Canadian aluminum products to protect U.S. industry from a “surge” in imports. Canada denies any impropriety.

“Everyone in Canada understands aluminum from Canada is no threat to national security in the United States,” Foreign Minister Francois-Philippe Champagne told reporters on Monday ahead of a cabinet retreat in Ottawa.

Champagne noted that Ottawa had slapped tariffs on a wide range of U.S. goods in 2018 after Washington imposed sanctions on Canadian aluminum and steel.

“It’s a formula that we have already used and it’s the formula that we’ll use this time as well,” he said. Freeland’s office said it could not confirm an announcement would be made on Tuesday.

($1=1.3173 Canadian dollars)