Washington suspends Fable 5 and Mythos 5 from Anthropic for foreign users

The U.S. government ordered on June 12, 2026 the immediate suspension of access to Fable 5 and Mythos 5, the two most advanced AI models from Anthropic, for all foreign nationals. The directive, issued under national security authorities, came just forty-eight hours after the commercial launch of Fable 5. What does this say about the regulatory trajectory of AI in the United States?

A directive 48 hours from the launch of Fable 5

Anthropic presented Fable 5 on June 10 as its most powerful publicly available model, designed for programming, finance, and long-context tasks. Two days later, Washington stopped everything.

According to Anthropic, the government did not provide detailed evidence to support its decision. However, the company claims that allegations of jailbreak on Fable 5 likely triggered the measure.

Upon review, it states that the technique in question only reveals a small number of minor vulnerabilities already listed, present in other competing systems.

Fable 5 had nevertheless undergone thousands of hours of testing conducted by U.S. government agencies, the British AI Security Institute, and private security teams. None identified a universal method to bypass the model’s protections.

Mythos 5 in the crosshairs, when the Glasswing project complicates everything

Mythos 5, the other suspended model, is even more sensitive. Deployed as part of the Glasswing project in partnership with the U.S. government, it relies on the same architecture as Fable 5 but operates with relaxed cybersecurity restrictions. Anthropic described it as having the most advanced cyber capabilities among AI systems available today.

The suspension is part of a broader context. The Trump administration reportedly also extended export restrictions on advanced AI models to foreign governments, companies, and individuals, according to information circulating for several days. 

The Mythos 5 case gathers concerns: a third party allegedly managed to hack the system, which reportedly directly fueled the government’s decision.

Anthropic also warns that recalling commercial AI systems for limited security reasons could create a dangerous precedent for the entire sector. A warning that takes particular importance as the company called, as early as June 5, for an international coordination on advanced AI.

In sum, the suspension of Fable 5 and Mythos 5 materializes in a few hours what Anthropic had theorized for weeks. States can now act quickly and strongly on AI models deemed strategic. A record launch, jailbreak allegations, a national directive, a global restriction. 

Anthropic says it is complying with the order while contesting it and is working to restore access. The outcome of this standoff will set the tone for the entire industry. Follow on Cointribune for the next developments.