Apple is expected to announce a $500 million commitment to MP Materials, the operator of the only U.S. rare earths mine, Fox Business reported on Tuesday, citing multiple sources familiar with the deal.

Apple and MP Materials did not immediately respond to Reuters requests for comment.

Shares of Las Vegas-based MP Materials jumped 12.3% to $54.50 in premarket trading.

MP agreed a multibillion-dollar deal last week with the U.S. government to boost output of rare earth magnets and help loosen China's grip on the materials used to build weapons, electric vehicles and many electronics.

The Fox Business report said the agreement includes plans for Apple to purchase U.S.-made rare earth magnets from MP Materials' Texas facility.

MP already produces mined and processed rare earths and has said it expects to start commercial magnet production at its Texas facility around the end of this year.

Fox Business also said the two companies will build another factory in Fort Worth, Texas to produce magnets and a new recycling facility in Mountain Pass, California.

Last week's deal with the U.S. Department of Defense includes a price floor for rare earths, designed to spur investment in domestic mines and processing plants, which has been lagging partly due to low prices set in China.

The DoD price guarantee for the two most popular rare earths was set at nearly twice the current market level.

(Reporting by Zaheer Kachwala in Bengaluru and Eric Onstad in London; Editing by Pooja Desai, Kirsten Donovan)