A global suspension of Anthropic’s Claude Fable 5 – triggered by Washington’s decision to block foreign access to what is widely regarded as the world’s most advanced artificial intelligence model – has prompted developers and businesses around the world to reassess their dependence on US technology, creating an opportunity for increasingly capable Chinese rivals.

Fable 5, unveiled on June 9 as the public-facing version of Anthropic’s powerful Claude Mythos model, remains unavailable worldwide after the US government ordered restrictions on foreign access, citing concerns that the model could be vulnerable to jailbreaking.

Rather than attempt to screen users by nationality, Anthropic disabled Fable 5 globally on June 12 to comply with the directive. The company said it disagreed with the government’s approach and was working to restore access as quickly as possible.

The US restrictions have fuelled debate over whether advanced AI models are becoming strategic assets subject to geopolitical controls, potentially accelerating interest in Chinese open-source alternatives even as US frontier models retain a significant technological lead.

“I think the Zhipu rally tells you the market immediately understood the opening that Anthropic just created,” said Lizzi Lee, a fellow on the Chinese economy at the Asia Society Policy Institute’s Centre for China Analysis.

Just one day after Anthropic cut off access to Fable 5, Beijing-based Zhipu AI launched its latest flagship model, GLM-5.2. Founder Tang Jie described the US restrictions as “deeply regrettable” in a post on X while highlighting the model’s fully open nature.