US stocks fell on Friday after President Donald Trump threatened a 35% tariff on Canada — a sharp escalation in an ongoing trade war.

President Donald Trump threatened a 35% tariff on some Canadian goods and raised the prospect of increasing levies on most other countries, ramping up his trade rhetoric in comments that weighed on stocks and boosted the US dollar.

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.