(Reuters) -MP Materials said on Thursday it has entered into a public-private partnership with the U.S. Department of Defense to build-out domestic rare earth magnet supply chain and reduce foreign dependency, sending shares up 30% in premarket trading.

The company will construct its second magnet manufacturing facility in the U.S., the '10X Facility', to serve defense and commercial customers.

Rare earths are a group of 17 metals used to make magnets that turn power into motion for electric vehicles, in cell phones, and other electronics.

China is the world's largest producer and earlier halted exports to counter U.S. moves to levy punishing tariffs on it.

MP Materials expects to add additional heavy rare earth separation capabilities at its California-based Mountain Pass facility.

"This initiative marks a decisive action by the Trump administration to accelerate American supply chain independence," said its CEO James Litinsky.

The facility is expected to be commissioned in 2028, the company added.

(Reporting by Katha Kalia in Bengaluru)