The Trump administration will not allow G7 member countries to regain access to Anthropic’s most advanced AI models after the US imposed a ban last week over national security concerns, sources told The Post. UK Prime Minister Keir Starmer requested a “carve-out” for British nationals and companies to Anthropic’s cutting edge “Mythos” and “Fable” AI models after the US on Friday announced export controls that barred its use by anybody outside the US or foreign nationals. Issuing any exemption would be “completely illogical,” a Trump administration official said. The insider said the US was working with Anthropic to ensure model safety. White House officials are negotiating with Anthropic over how to resolve the ban. A senior White House official suggested a resolution could be worked out directly with CEO Dario Amodei. The controversy erupted last week when Anthropic said the Commerce Department ordered it to block access outside the US and for foreign nationals. In response, the company disabled Fable 5 and Mythos 5 globally, claiming it could not restrict models to US-only users. Anthropic said the government cited a potential “jailbreak” that could let models identify software vulnerabilities, which the company described as “narrow.” Anthropic rejected the broad action.