In a surprising reversal of the United States’ years-long technology restrictions on China, President Donald Trump last month allowed Nvidia to resume sales of a key AI chip designed specifically for the Chinese market.

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. Sales of the chips to Chinese companies helped get China to agree to reboot its exports to the U.

Trump said Monday that he has cut a deal with chipmaker Nvidia, allowing it to sell certain artificial intelligence chips to China in exchange for a cut of the revenue, which would go to the U.S. government. Trump said he also negotiated a similar deal with chipmaker Advanced Micro Devices (AMD).