S&P 500 futures lost 0.5%, while Nasdaq 100 futures dropped 0.6%. Futures for the Dow Jones Industrial Average fell 204 points, or 0.5%.

President Donald Trump released two tariff letters on Saturday, imposing duties of 30% on products from Mexico and the European Union.

Kristi Noem says Trump wants FEMA 'remade,' and more tariffs are set for U.S. trade partners: Weekend Rundown Homeland Security Secretary Kristi Noem said President Donald Trump wants the Federal Emergency Management Agency “remade” rather than dismantled entirely.

President Donald Trump posted letters to the leaders of Mexico and the European Union, saying they had not done enough to head off the new tariffs.

The European Union braced on Friday for a possible letter from U.S. President Donald Trump outlining planned duties on the United States' largest trade and investment partner after a broadening of his tariff war in recent days.

President Trump said he plans to impose blanket levies of 15% to 20% on most trading partners that haven't yet received suggested tariff rates. That would be higher than the 10% baseline currently in effect.

It shows that personal grudges rather than simple economics are a driving force in the U.S. leader’s use of tariffs.

Major stock indexes were slightly lower on Friday as U.S. President Donald Trump's announcement of tariffs on imports from Canada fanned worries about trade tensions, with the Canadian dollar down against the greenback.