Artificial intelligence company Anthropic and the Trump administration are sparring — yet again.

Over the weekend, tensions between the San Francisco company and the Trump administration flared up after the U.S. government ordered Anthropic to cut off foreign access to the company’s most powerful AI systems.

The government’s order poses a challenge to Anthropic’s business and its branding, which focuses heavily on AI safety. The company said it disabled access to its most advanced models for all its customers to comply with the directive. Customers still have the ability to access other Anthropic models.

The unusual move came days after Anthropic released the AI models, known as Fable 5 and Mythos 5. Anthropic limited the release of Mythos 5, which can be used to fix software vulnerabilities, to a “small group of cyberdefenders and infrastructure providers” amid concerns that hackers could exploit the tool to break into computer networks.

Fable 5 excels in software engineering, scientific research and other complex tasks, according to the company. Now, Anthropic is facing security concerns around the release of that model.

Anthropic is competing with other major tech companies to advance AI. Anthropic filed to go public and its valuation is nearly $1 trillion, surpassing its rival OpenAI.

Here’s what you need to know about the latest high-stakes public spat:

Why did the U.S. government order Anthropic to cut off foreign access to its latest AI models?

Anthropic said in a blog post on Friday that the government raised national security concerns but didn’t provide details.

“Our understanding is that the government believes it has become aware of a method of bypassing, or ‘jailbreaking’ Fable 5,” the company said in the post. Anthropic said that there are safeguards in place to prevent the AI system from being misused for cybersecurity tasks and that no tester has been able to broadly bypass these guardrails.

The company added that it worked with the U.S. government ahead of the model’s launch.

But David Sacks, a venture capitalist who served as the Trump administration’s crypto and AI advisor, accused Anthropic of prioritizing “the continued offering of the consumer model over safety.”

The Trump administration, he said, wants to resolve this safety issue and then access to Fable can be restored.

“The Admin wants all of this to happen as soon as possible. It is frankly bewildered that Anthropic hasn’t wanted to comply with safety requests that it previously said were its highest priority,” he wrote.

Over the weekend, Trump officials also took jabs at Anthropic, escalating the public feud.

“Three months ago, @DeptofWar kicked @AnthropicAI out of our building — forever,” Defense Secretary Pete Hegseth said on X. “Every passing day proves why that was the right move.”

What prompted the government to issue this order?

Conversations that Amazon Chief Executive Andy Jassy had with the Trump administration’s officials including Treasury Secretary Scott Bessent triggered the president’s order, people familiar with the matter told the Wall Street Journal.

Amazon researchers were able to get Anthropic’s Fable 5 model to provide information that could be used to help cyberattackers, according to the report. An Amazon spokesperson told the news outlet that “it’s not uncommon for governments to seek our counsel on potential security risks.”

Amazon has also invested billions in Anthropic and supplies them with chips to train their AI models.

Anthropic said it’s complying with the government order but disagrees that the finding “should be cause for recalling a commercial model deployed to hundreds of millions of people.”

“If this standard was applied across the industry, we believe it would essentially halt all new model deployments for all frontier model providers,” the company said.

Have Anthropic and the Trump administration sparred before?

Yes, but it involved a different issue.

Anthropic and the Pentagon were fighting over language involving a $200-million government contract with the company. Anthropic wanted more guarantees that its tech wouldn’t be used for surveillance of Americans or autonomous weapons. But the Pentagon viewed the pushback as an attempt by Anthropic “to seize veto power over the operational decisions of the United States military.”

In February, Trump directed federal agencies to stop using technology from Anthropic, calling the company “radical left” and “woke.”

Anthropic sued the Trump administration seeking to reverse its designation as a “supply chain risk” and accused the government of illegally retaliating against the company.

What’s next?

Anthropic and the White House are trying to resolve concerns brought up about the AI models.

Senior technical staff at Anthropic were in Washington, D.C., on Monday and were expected to meet with White House officials, a source familiar with the matter told The Times.

A Trump administration official said the meeting was to happen in the Commerce Department. The department didn’t immediately respond to a request for comment on the meeting.