China's government told operators of "critical information infrastructure" to stop buying Micron Technology's products Sunday and claimed the U.S. chipmaker threatened national security.

Driving the news: The Cyberspace Administration of China's claims, which a U.S. Commerce Department spokesperson in a statement to media Sunday evening said had "no basis in fact," followed a security review of the Idaho-based firm.

• The CAC in a statement claimed Micron failed the review, which it said posed "a major security risk" to China's "key information infrastructure supply chain" and threatened the country's national security.
• The statement did not detail any specific risks.

What we're watching: Micron said in a statement to news outlets it's "evaluating the conclusion" of the CAC report, assessing next steps and looked forward to "continuing to engage in discussions with Chinese authorities."

What they're saying: The Commerce Department spokesperson said it "firmly" opposed the restrictions on Micron.

• "This action, along with recent raids and targeting of other American firms, is inconsistent with [Beijing's] assertions that it is opening its markets and committed to a transparent regulatory framework," the spokesperson added.

The big picture: The CAC's investigation into Micron and its findings come as the U.S. and other democracies accelerate a tech decoupling from China, with the United States, Japan and United Kingdom last week announcing major chip and quantum computing investments.

• The Biden administration last October imposed export restrictions aimed at hobbling Beijing's ability to make advanced semiconductors, and the Netherlands and Japan later greatly curtailed their exports of leading-edge chipmaking gear to China.
• In December, the Biden administration added the memory chipmaker YMTC and other Chinese firms to a trade blacklist.

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Editor's note: This article has been updated with new details throughout.