The US government has rolled back export restrictions imposed on Anthropic's Fable and Mythos artificial intelligence models, marking a significant reversal less than three weeks after the company was directed to halt access to its most advanced systems over national security concerns.US lifts curbs on Anthropic's Fable, Mythos AI models. (REUTERS (File))The decision comes as Washington continues to tighten scrutiny of cutting-edge AI technologies, reflecting growing concerns that powerful AI models could be exploited by military or intelligence entities in countries such as China and Russia.Export restrictions liftedAnthropic confirmed on Tuesday that the US Commerce Department has withdrawn the export controls on its Fable and Mythos models.The company said it would begin restoring access to the models from Wednesday."We'll begin restoring access tomorrow," Anthropic said in a statement on X.The move follows an earlier order issued on June 12 that forced the company to suspend access to its Mythos 5 and Fable 5 models because of export-control requirements.Government eases its earlier orderThe latest decision expands on a partial relaxation announced last week.On Friday, the US government had allowed Anthropic to make Mythos 5 available to a limited group of "trusted" US organisations, easing some of the earlier restrictions while broader export controls remained in place.Now, according to a letter from US Commerce Secretary Howard Lutnick seen by Reuters, those export controls have been withdrawn altogether.Lutnick wrote that a licence is no longer required for the export of the Mythos or Fable models.Security commitments from AnthropicThe withdrawal of the restrictions comes after Anthropic agreed to work closely with the US government on AI security measures."Anthropic has agreed to proactively detect and address security risks associated with the models; to work diligently with the US government on protocols and standards and releases for Mythos, Fable, and future models; and to inform the US government of any malicious activity," Lutnick said.The US government's role in deciding which organisations can access advanced AI models has sparked criticism within the technology industry.OpenAI CEO Sam Altman questioned the approach last week in a post on X."Extensive safety testing is not a bad idea. I just don't like the idea of the government picking the customers."(With Reuters inputs)