Tesla CEO Elon Musk is seeking permission from China to use rare earth magnets.

Tesla's Optimus robot production program is reportedly being disrupted by China's rare earth export restrictions.

On Tuesday, Musk said during an earnings call that Optimus production was being affected by "the magnet issue."

"We're working through that with China. Hopefully, we'll get a license to use the rare-earth magnets," Musk, who is also a White House adviser, said.

He said, "China wants some assurances that these are not used for military purposes, which obviously they're not. They're just going into a humanoid robot."

In response to the U.S. "reciprocal tariffs," on April 4, China's Ministry of Commerce, in conjunction with the General Administration of Customs, announced a decision to impose export controls on seven categories of medium and heavy rare earth-related items, including samarium, gadolinium, terbium, dysprosium, lutetium, scandium, and yttrium.

A spokesperson for the Ministry of Commerce said that the items in question had dual-use properties and that it was common international practice to impose export controls on them.

It is worth noting that rare earths, though niche, have important uses in optical laser technology, radar equipment, wind turbine magnets, jet engine coatings and other advanced technologies.

Musk's big complaint was inevitable when rare earths were restricted from entering the U.S. So, he's looking to the people who started it to fix it.