US stock market futures were tending down Sunday, one day after President Donald Trump announced 25% tariffs on Canada and Mexico and 10% tariffs on China.

Stock futures tumbled Sunday night to kick off a new trading month, as investors weighed new U.S. tariffs on goods from key trade partners and their potential impact on the economy and corporate profits.

Wall Street opened lower after Trump's tariffs on Mexico, Canada and China, sparking fears of trade wars that'll slow economies and ignite inflation.