The United States has made a unilateral decision to drop the 10% tariffs on Canadian non-alloyed unwrought aluminum exports to the U.S., retroactive to September 1, 2020. The US expects that trade of these goods will normalize in the last four months of 2020. The US set monthly targets for acceptable volumes of aluminum imports from Canada without tariffs and may re-impose the tariffs if shipment volumes exceed 105% of the monthly shipment volumes.
Canada was prepared to impose 10% Surtax countermeasures on various US aluminum import products, effective September 16, 2020, but has since withdrawn this planned retaliation. The Canadian Government has declared to the USTR (United States Trade Representative), that if they were to impose tariffs in the future, Canada will retaliate with dollar-for-dollar reciprocal countermeasures.
For further details, reference the below source links:
USTR Statement on Canadian Aluminum
CBC News: U.S. calls off tariffs on Canadian aluminum —for now
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