The rebuke of President Trump’s tariff plans came just days before sweeping tariffs on Canada and Mexico were expected to go into effect.

Warren Buffett says tariffs are “an act of war, to some degree.” Berkshire Hathaway’s chairman and chief executive said the country has had a lot of experience with tariffs, and that over time they are a tax on goods.

Warren Buffett broke his silence on President Trump’s trade policies, comparing his planned tariffs on Canada and Mexico to an “act of war.” The legendary investor behind Berkshire Hathaway — which has large businesses in insurance,