President Trump on Thursday announced new tariffs on imported steel and aluminum, but Mexico and Canada — the largest exporter of both metals to the US — would be exempt from the levies.

The tariffs — 25 percent on steel and 10 percent on aluminum — will take effect in 15 days.

But any other country that does business with the US will also be able to negotiate deals that could exempt them, including Australia, according to the president.

“You don’t have steel, you don’t have a country. Our industries have been targeted for years and years, decades, in fact, by unfair foreign trade practices, leading to the shuttered plants and mills, the layoffs of millions of workers and the destruction of entire communities, and that’s going to stop,” the president said from the Roosevelt Room at the White House.

Trump made the announcement while surrounded by steel and aluminum workers “from the heartland,” a senior administration official said.

The president wants to protect jobs and also argues that national security is at stake.

Commerce Secretary Wilbur Ross told Fox Business that other countries would be exempt if it served US national security interests.

“It’s defined to include effect on employment. It’s defined to include effect on individual industries. It’s not the conventional definition of national security,” he said.

The European Union has slammed the proposal, and threatened retaliatory taxes on Harley-Davidson motorcycles, Kentucky bourbon, Florida orange juice and Wisconsin cranberries, among other items.

The tariffs could also be slapped on Canada and Mexico if negotiations over NAFTA and other security issues don’t achieve the results the president is looking for.