The Biden administration is considering tighter controls on the export of artificial intelligence chips to China, as it worries about how rivals might use the powerful technology. The WSJ reports that the US commerce department could introduce restrictions next month that would stop companies like Nvidia selling advanced chips to customers in China and other countries of concern without first obtaining a licence, after initial export controls were announced last October. Nvidia has already made a less advanced chip for the Chinese market, the A800, to comply with the earlier restrictions. Jake Sullivan, the US national security adviser, has described the US approach as creating a “high fence” around a “small yard” around critical technologies such as artificial intelligence.