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.

If a 30 percent tariff on Mexico goes into affect on August 1, a wide variety of foods will be more expensive, experts warn.

Financial markets, which have shown increasing insensitivity to tariff threats from the US, will face a test at the Monday open after President Donald Trump declared a 30% rate for the European Union and Mexico effective Aug.

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

President Trump warns Canadian Prime Minister Mark Carney of a new 35% tariff on Canadian imports if the country doesn't address fentanyl trafficking and existing trade disputes.

U.S. President Donald Trump has launched a global trade war with an array of tariffs that target individual products and countries. Trump has set a baseline tariff of 10% on all imports to the United States,