Anthropic said it blocked its most advanced artificial intelligence models for public use after the U.S. government banned their use by foreigners.

Anthropic released its Fable 5 and Mythos 5 models earlier this week, advertising them as the most advanced AI models given to the public to date. On Friday, the company received a directive from the U.S. government banning the models’ use by any foreign national, citing concerns over an alleged method to “jailbreak,” or bypass, the models’ security features. To comply with the demand, Anthropic suspended use of the model for all users, claiming that was the only way to cooperate with the order.