
Just days after its launch, Anthropic has now suspended access to both Claude Fable 5, as well as its more advanced Mythos 5 model, following an export control directive issued by the US government. In a recently published statement, the AI firm said the directive requires the company to suspend access to both models for all foreign nationals, regardless of whether they are located inside or outside the United States.
The order also applies to foreign-national employees working at Anthropic itself. As a result, the company says it had no choice but to disable Fable 5 and Mythos 5 access for all customers worldwide in order to comply with the directive. The company’s other AI models, meanwhile, remain unaffected.

US Cites National Security Concerns
According to Anthropic, the government did not provide detailed information regarding the national security concerns behind the order. However, it believes the directive stems from concerns that someone may have discovered a way to bypass or “jailbreak” Fable 5’s safeguards.
The firm disputes the severity of the issue, saying it reviewed the demonstration in question and found that it only exposed a small number of previously known and relatively minor software vulnerabilities. It also claimed that other publicly available AI models were capable of identifying the same vulnerabilities without requiring any jailbreak technique.
The move marks one of the most significant attempts by the US government to directly restrict access to frontier AI models. According to reports, US Commerce Secretary Howard Lutnick informed Anthropic that both Fable 5 and Mythos 5 would be subject to export controls governing access by foreign governments, companies, and non-US individuals. The restrictions reportedly apply not only to users outside the country but also to foreign nationals residing within the United States.

Just Days After Fable 5 Launch
As mentioned earlier, Fable 5 was launched only earlier this week as Anthropic’s first Mythos-class model made broadly available to the public. The company positioned it as a safer and more accessible version of Mythos 5, incorporating safeguards that automatically redirected high-risk requests involving areas such as cybersecurity and biosecurity to less capable models.
Anthropic has maintained that it remains committed to working with the US government to address concerns surrounding the models. It described the directive as a misunderstanding and said it hopes access to Fable 5 and Mythos 5 can be restored as soon as possible.
This latest development also arrives shortly after Anthropic publicly advocated for a global framework that would allow governments to temporarily pause the development or deployment of highly capable AI systems if they are deemed to pose severe risks. At the time, the company argued that frontier AI models were approaching a level where stronger oversight mechanisms could become necessary.
(Source: WSJ / Anthropic [official website])