Mexico and the European Union have responded quickly to the United States’ decision to impose steel and aluminum import tariffs.

European Commission President Jean-Claude Juncker called the decision “protectionism, pure and simple.”

Mexico, meanwhile says it will answer the tariffs with duties of its own on a variety of U.S. products, including pork bellies, apples, grapes, cheeses and flat steel among other things.

Juncker says the EU will also respond with countermeasures.

He says the U.S. action leaves the EU with no choice but to proceed with a case in the World Trade Organization. He says the EU will impose additional duties on a number of imports from the U.S.

A statement from Mexico's economy ministry says the U.S. use of a national security justification is improper and that the tariffs affect strategic sectors for North America, including automotive, aerospace and electronics.

Trump announced the tariffs in March, but gave exemptions to the European Union, Mexico and Canada.