The Pentagon "is looking forward to continue working with companies across the (rare earths) supply chain to ensure that DoD and the nation have the secure and resilient supply chains necessary to secure national and economic security for generations to come," the official said.

MP Materials, which runs the only American rare earths mine, announced a new $500 million agreement with tech giant Apple on Tuesday to produce more of the powerful magnets used in iPhones as well as other high-tech products like electric vehicles.

Apple Inc. has struck a $500 million deal to buy rare-earth minerals from MP Materials Corp., the US producer that just last week secured backing from the Pentagon.