China state media is calling for Nvidia Corp. to prove that its H20 chip is secure, saying it can’t allow flawed chips into the country.China’s top internet watchdog summoned Nvidia representatives earlier this week to discuss what Chinese officials called significant security vulnerabilities in the H20.

Washington in July cleared Nvidia to resume sales of the H20 chips to China, reversing an effective April export ban. Beijing has since sought supporting documentation on potential risks, including vulnerabilities,

Nvidia earlier this month said the U.S. government is giving permission to sell its H20 microchip again in China — but now a Chinese regulator is raising a red flag.