Nvidia’s artificial-intelligence chips have been at the center of U.S.-China trade negotiations for months, yet it appears China is discouraging its companies from buying one of them: the H20s. Why? Sales of the chips to Chinese companies helped get China to agree to reboot its exports to the U.

China has urged local companies to avoid using Nvidia Corp.’s H20 processors, particularly for government-related purposes, complicating the chipmaker’s attempts to recoup billions in lost China revenue as well as the Trump administration’s unprecedented push to turn those sales into a US government windfall.