(KLZA)-- The company that wants to mine for critical minerals in southeast Nebraska has signed a deal with Stellantis, giving the automaker access to the rare earth elements used to produce high-powered magnets needed for its electric vehicles.

NioCorp announced the tentative deal Thursday. The companies didn't disclose how much Stellantis will pay because those details are still being negotiated, but this deal with such a high-profile buyer will likely provide a boost to NioCorp's effort to raise $1.1 billion to build the mine.

Stellantis automobile makers brands include Chrysler, Alfa Romeo and Maserati on Thursday.

NioCorp is still working to determine whether it will be make economic sense to produce the rare earth elements present at the site near Elk Creek. The proposed mine's main product would be niobium that's used to make steel lighter and stronger.

But most of the rare earth elements available today are produced in China, so President Joe Biden has been pressing for more of them to be mined domestically.

Currently, America imports all the niobium and scandium and most of the titanium and rare earths that NioCorp hopes to produce. The only U.S. mine that produces rare earths now is run by MP Materials in Mountain Pass, California.

NioCorp CEO Mark Smith said “This could really turbocharge our project financing and help to accelerate moving the project to construction and eventual commercial operation.”