China says products made by US memory chip giant Micron Technology are a national security risk.

The country’s cyber regulator announced on Sunday that America’s largest memory chip maker poses a “serious cybersecurity risk”.

That means the company’s products will be banned from being used in critical infrastructure projects in the world’s second-largest economy.

It is China’s first major move against an American chipmaker, amid rising tensions between Beijing and Washington.

The CAC did not provide details about what risks it said it found or what Micron products it found.

A spokesperson for Micron confirmed to the BBC that the company “received notice from CAC after reviewing Micron products sold in China”.

“We are evaluating the conclusions and assessing our next steps. We look forward to continuing to engage in discussions with the Chinese authorities,” they added.

In response, the US government said it would work with allies to address what it calls “the distortion of the memory chip market caused by China’s actions”.

“We firmly oppose restrictions that have no basis in fact,” said a spokesman for the US Department of Commerce.

“This action, along with recent attacks and targeting on other US companies, is inconsistent with [China’s] affirms that it is opening its markets and is committed to a transparent regulatory framework,” it added.

The announcement from the CAC is the latest development in an ongoing dispute between Washington and Beijing, which has seen the US impose a number of measures against China’s chipmaking industry.

On Sunday, US President Joe Biden said the G7 nations were looking to “minimize risk and diversify our relationship with China.”

“That means taking steps to diversify our supply chain,” he added.

Micron CEO Sanjay Mehrotra attended the summit in Hiroshima as part of a panel of business leaders.

Last week, the company said it would invest around 500 billion yen ($3.6 billion; £2.9 billion) to develop the technology in Japan.