Anthropic has responded after the Trump administration issued a directive banning foreign nationals from using some of its most powerful AI tools, saying it would comply with the order but that it disagreed with the reasoning behind it.
In a blog post late on Friday evening, the company said it had received a letter from the government at 5:21pm ET requiring it to suspend access to its Fable 5 and Mythos 5 AI models over national security concerns.
The ban applies to foreign nationals both inside and outside the US and includes foreign national Anthropic employees, Anthropic said.
"The net effect of this order is that we must abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance," it continued. "Access to all other Anthropic models will not be affected".
The company has apologised for the disruption to users and said it is working to restore access as soon as it can.
Anthropic said its understanding was that authorities had become aware of a potential means of jailbreaking Fable 5. An AI jailbreak is when a hacker exploits vulnerabilities in an AI model, bypassing its ethical guidelines in an attempt to carry out restricted actions.
The company sought to play down the issue, saying that the vulnerabilities appeared to be "relatively simple" and that it had found publicly available models were able to identify them.
It added that while it was complying with the directive, it disagreed that a "narrow potential jailbreak should be cause for recalling a commercial model deployed to hundreds of millions of people".
Anthropic also stressed that it had developed "strong safeguards that greatly reduce the likelihood that Fable is misused for tasks related to cybersecurity".
Responding to the news on X, Jordan Bardella, a Member of the European Parliament and president of France's far-right National Rally party, said the move was a sharp reminder that artificial intelligence is a "major issue of national sovereignty".
"Nations that do not quickly develop their own model(s) will always depend more and more on the choices of other powers: France must accelerate its support for the gem Mistral AI and the entire AI ecosystem," he added.
Tom Tugendhat, a British MP and former security minister, said it showed how technology has become increasingly central to sovereignty.
"Disabling Fable 5 and other models for foreigners is not a misunderstanding or a mistake, it’s the inevitable result of technology shaping warfare so that sovereignty is more about code than cannons," he wrote on social media.
It is not the first time Anthropic and the Trump administration have clashed.
In February, Trump directed US federal agencies to immediately stop using Anthropic's technology after CEO Dario Amodei and his firm objected to its technology being used for certain defence purposes.
"We don’t need it, we don’t want it, and will not do business with them again!," Trump wrote on Truth Social at the time, saying there would be a "phase out period" of six months.
Anthropic later announced it would be taking legal action against the government after it also designated the company a "supply chain risk".