About four days after Anthropic released Claude Fable 5, a next-generation "Mythos-class" AI model, the frontier AI lab led by Dario Amodei revealed late Friday that it was disabling foreign customers' access to these cutting-edge models, citing an export-control directive from the federal government."The US government, citing national security authorities, has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States, including foreign national Anthropic employees," Anthropic wrote on X around 9 p.m. ET.The AI lab's website stated that the federal directive was received around 5:21 p.m. ET. To ensure compliance, the lab was forced to shut off Fable 5 and Mythos 5 for all customers.Anthropic continued, "The net effect of this order is that we must abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance. Access to all other Claude models is not affected."The US government, citing national security authorities, has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States, including foreign national Anthropic employees.