(Fox News) President Trump signed an order Thursday that imposes tariffs on steel and aluminum imports from all foreign countries, while carving out an exception for Canada and Mexico for now while North American Free Trade Agreement (NAFTA) negotiations are under way.

The president, joined by steel and aluminum workers, signed a companion proclamation — one on steel and one on aluminum – instituting a tariff of 25 percent on steel and 10 percent on aluminum imports. The tariffs will become effective in 15 days, with exclusions for Mexico and Canada taking effect “immediately,” officials said.

“You are truly the backbone of America, you know that. Very special people,” Trump told the workers. “We have to protect our steel and alumnium industries while at the same time, showing great flexibility with people who are really friends of ours.”

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