TechnologyWhite House reportedly asks OpenAI and Anthropic to withhold new models from UK testers until US review
POLITICO reports that Anthropic appears to have agreed so far. A senior US official told the outlet Washington wants to review the models and take steps to secure US systems before sharing them with partners.
TLDR
POLITICO reported on September 24, 2026, citing a person familiar with the matter and a senior US administration official, that the Office of the National Cyber Director asked OpenAI and Anthropic to let the US government test new models before sharing them with the UK's AI Security Institute. The outlet says Anthropic appears to have agreed so far; the institute did not receive Claude Mythos 5.1. Anthropic said it was coordinating with the US government to broaden access beyond a set of US organizations. AISI's director said it still had prerelease access to some leading models and had tested OpenAI's GPT-6 Astra before release.
White House reportedly asks OpenAI and Anthropic to withhold new models from UK testers until US review
POLITICO reports that Anthropic appears to have agreed so far. A senior US official told the outlet Washington wants to review the models and take steps to secure US systems before sharing them with partners.