Nvidia chief Jensen Huang has condemned US export controls designed to limit China’s access to artificial intelligence chips as “a failure” that spurred Chinese rivals to accelerate development of their own products.

Nvidia CEO Jensen Huang criticized U.S. export controls blocking the sale of its AI chips to China. Last month, the chipmaker noted a $5.5 billion write-down to its inventory, after the U.S. demanded companies get a license to sell their AI chips to China.

Washington’s efforts gave Chinese companies “the spirit, the energy and the government support to accelerate their development,” said Jensen Huang.