Anthropic said it plans to disable access to its latest top AI models, Fable 5 and Mythos 5, following a government export control that would bar foreign individuals and entities from using the products.
The company said in a blog post on Friday evening that it had received a letter from the US government at around 5:21 p.m. ET, citing national security concerns regarding Anthropic's models.
Anthropic said the government's order included any foreign national inside or outside the US, "including foreign national Anthropic employees," and that the "net effect" of the order is to disable the models for everyone to ensure compliance.
The company added that the letter "did not provide specific details of its national security concern."
Anthropic said it believes the government's concern is a potential way to "jailbreak" Fable 5, but disputed the issue's severity. The company said the technique appeared narrow, not universal, and involved known vulnerabilities that could be identified by other publicly available models.
The move marks the latest escalation in Anthropic's clash with the Trump administration over AI safety, national security, and the extent of government control over frontier AI models.
In** **February, the Pentagon moved to designate Anthropic as a supply chain risk after the startup sought limits on its AI model for certain defense applications.
Anthropic sued the Defense Department over the designation. Two lawsuits related to the government's supply-chain risk label remain pending.
A White House spokesperson did not immediately respond to a request for comment.
Anthropic said it was complying with the order but disagreed with the government's finding. An Anthropic spokesperson did not say when exactly the company would disable access.
Access to Anthropic's other models will not be affected, the company said.