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.

President Donald Trump has posted two new letters on his social media platform announcing tariffs on the European Union and Mexico.

U.S. President Donald Trump on Saturday announced he's levying tariffs of 30 percent against the European Union and Mexico starting Aug. 1, a move that could cause massive upheaval between the United States and two of its biggest trade partners.

The European Union has decided to hold off on imposing retaliatory tariffs on U.S. goods that were set to begin Monday.

U.S. stock futures fell Sunday, a day after President Donald Trump threatened to impose new 30% tariffs against imports from Mexico and the European Union.