The Trump administration told AI developers on Tuesday that it will not put open-weight AI models through voluntary safety tests, according to two sources familiar with the discussions. Open models, including Nvidia's Nemotron and Meta's Llama, are AI systems with publicly accessible core components, while closed models are controlled by specific companies such as OpenAI, Google and Anthropic. The White House discussed the unpublished testing rules with staff from Meta, Anthropic, Google, Nvidia and OpenAI, according to five sources familiar with the meeting. The meeting follows disclosures from OpenAI and Anthropic that their AI tools breached the systems of other companies, raising concerns among U.S. lawmakers about whether increasingly capable AI models could be used to conduct or facilitate cyberattacks. OpenAI on Tuesday said the company's models were involved in another cybersecurity incident during testing and that the situation involved AI systems accessing the internet. Tech policy advocacy group Americans for Responsible Innovation said sharing the framework with a small group of companies without making it public "deepens a serious gap in federal oversight." The Trump administration said in June the tests would be voluntary and designed for AI models with sophisticated hacking capabilities. Five Democratic senators called on Trump on Tuesday to work with Congress to pass legislation making testing permanent for the most advanced American-made AI models, called "frontier models." The senators said the United States cannot afford a policy environment with opaque restrictions while Chinese alternatives appear cheaper and easier to access. The White House's media office did not respond to a request for comment.