President Donald Trump late Thursday threatened a 35% tariff on goods imported from Canada, a dramatic escalation in an on-again, off-again trade war with America’s northern neighbor and one of its most important trading partners.

President Donald Trump said the U.S. will impose a 35% tariff on all Canadian goods from Aug. 1 and threatened a blanket 15 to 20% levy on most other nations.

U.S. President Donald Trump said on Thursday the United States would impose a 35% tariff on imports from Canada next month and planned to impose blanket tariffs of 15% or 20% on most other trade partners.