President Donald Trump said the US will put a 35% tariff on some imports from Canada, escalating the tensions between two countries that have impaired one of the world’s largest trading relationships.

U.S. President Donald Trump on Thursday signed an executive order increasing tariffs on Canadian goods to 35% from 25% on all products not covered by the U.S.-Mexico-Canada trade agreement, the White House said.

Canada faces steep 35% tariffs on almost 60% of its U.S. imports — if President Trump follows through tomorrow on his Aug. 1 deadline for imposing the extraordinary duty.