US government pressures OpenAI to delay GPT-5.6 rollout after Anthropic's Claude Mythos suspension, citing need for pre-release review.

The U.S. government is moving to ensure that its latest, most advanced AI tools cannot be used against it. During a staff Q&A meeting, OpenAI CEO Sam Altman disclosed that GPT-5.6 is currently available only in limited preview to a small group of customers handpicked by the federal government. According to The Information, the Office of the National Cyber Director and the Office of Science and Technology Policy asked OpenAI to stagger the model's release. While Altman did not specify how long the delay would last, he indicated in a memo that he hoped the general release would occur within a couple of weeks. In the interim, the government is granting access on a case-by-case basis only.

Despite OpenAI's compliance with the staggered timeline, sources report that Commerce Secretary Howard Lutnick called Altman to caution him against releasing GPT-5.6 to the public without prior government approval. In a Thursday memo, Altman responded: "We've made clear to the U.S. government that this is not our preferred long-term model and will work with them and others in industry to achieve a more sustainable approach for future releases."

This pattern mirrors Anthropic's experience. In early April, Anthropic released Claude Mythos Preview to select institutions to prepare for broader rollout. The company subsequently built Fable 5, a modified version with built-in safeguards, and released it in June 2026. However, the U.S. government disagreed that Fable 5 represented a safer model and placed both Fable 5 and Mythos on an export control list just three days after launch, banning foreign nationals—including Anthropic employees—from accessing the models. Unable to enforce compliance, Anthropic withdrew both models from the market entirely.

The White House's intensified oversight reflects broader competitive concerns with China. Although the Trump administration initially promised reduced AI regulations, President Donald Trump signed an executive order earlier this month requiring U.S. AI labs to provide government access to their latest models 30 days before public release.

The escalation has drawn criticism from industry voices. Neil Chilson, Head of AI Policy at the Abundance Institute and former FTC Chief Technologist, voiced concern on his blog: "This escalation of government intervention is nothing to celebrate. It is horrible for the broader AI ecosystem. Continued arbitrary, unexplained deployment of export control authority will make companies slow-walk new models, depriving the public of powerful new tools. Every AI model, like all software before it, will have vulnerabilities that require patching. The US government should not hang a Sword of Damocles over every lab's head, with no indication when it might drop or why."