President Donald Trump says he will not impose quotas on importing uranium, backing away from a possible trade confrontation and breaking with a Commerce Department assessment that America’s use of foreign uranium raises national security concerns.

The decision is unusual for Trump, who has pointed to national security concerns in calling for restrictions on foreign metal and autos in trade negotiations. It’s also drawing rare criticism from Republicans in energy-rich states.

Uranium is a vital component for the U.S. nuclear arsenal, submarines and power plants, which prompted a monthslong Commerce Department investigation into whether such materials fall under the national security umbrella.