Anthropic Disables Advanced AI Models After US Order Blocking Foreign Access

Jun 13, 2026

AI firm Anthropic has disabled its most advanced models, Fable 5 and Mythos 5, for all users after a US government order blocked access for foreign nationals over national security fears. The government cited a potential "jailbreak" vulnerability, a claim Anthropic disputes. The move escalates tensions following Anthropic's refusal to allow military use of its AI, and comes as the company prepares for an IPO.

US export control directive

▪The US government ordered Anthropic to suspend access to its Fable 5 and Mythos 5 AI models for all foreign nationals, citing national security concerns.
▪The order is a major escalation in US policy, which previously focused on controlling AI chips and tools rather than the AI models themselves.
▪A US official confirmed the Commerce Department issued the export control directive to suspend access to the models by foreign nationals.
▪The ban affects foreign nationals even if they are in the US; former official Dean Ball suggested users may need to prove citizenship.

Jailbreak vulnerability concerns

▪Anthropic stated it was only given "verbal evidence of a potential narrow, non-universal jailbreak" and disagreed it was cause for a recall.
▪The government believes a "jailbreak" method exists that could bypass safeguards and allow Fable 5 to be used for identifying software vulnerabilities.
▪The Fable 5 model has safeguards blocking its cybersecurity capabilities, while Mythos 5 is the non-public full version for government and corporate partners.

Anthropic-government tensions

▪The government previously placed Anthropic on a supply chain blacklist, set to take effect later in the year, in response to the company's refusal.
▪Anthropic confidentially filed for a US IPO last month, ahead of rival OpenAI.
▪Days before the order, Anthropic had called for greater US government oversight of AI, including the power to block models with unacceptable risks.
▪Anthropic's relationship with the US government was strained after the company refused to let the military use its AI for domestic surveillance or autonomous weapons.
▪Pentagon CIO Kirsten Davies supported the order, stating national security is more important than revenue or pre-IPO valuations.

Model access restrictions

▪Several key Anthropic personnel, including co-founder Chris Olah, were born outside the United States.
▪Access to all other Anthropic models is not affected by the directive.
▪Anthropic believes the situation is a "misunderstanding" and is working to restore access as soon as possible.
▪Amazon's cloud unit AWS confirmed it was asked by Anthropic to revoke access to the models for "all users in all regions."
▪To comply, Anthropic "abruptly disabled" its Fable 5 and Mythos 5 models for all users, not just foreign nationals.

Cybersecurity threat implications

▪Experts warned that Mythos-class models could accelerate sophisticated cyberattacks, particularly against sectors like banking, if misused.
▪Anthropic warned that applying this standard industry-wide could halt all new frontier model deployments.
▪Anthropic stated that models from rival AI providers have a similar ability to find minor bugs in code.