The European Union vowed to respond to 25% tariffs President Donald Trump said the US will impose on steel and aluminum imports, escalating a potential trade dispute with one of Washington’s closest allies.

The president said he planned sweeping tariffs on all steel and aluminum imports on Monday and would take other action to even out tariff rates with the rest of the world later this week.

“Any steel coming into the United States is going to have a 25% tariff,” he told reporters Sunday on Air Force One as he flew from Florida to New Orleans to attend the Super Bowl. When asked about aluminum, he responded, “aluminum, too” will be subject to the trade penalties.