The United States is planning to restrict China’s access to American cloud-computing services in a bid to prevent Chinese firms from evading controls on their use of advanced chips, the Wall Street Journal reported on Tuesday.

If the rule comes into force, US cloud-service providers like Amazon and Microsoft would need government permission to provide cloud-computing services that use advanced artificial-intelligence chips to Chinese customers, the WSJ report said, citing people familiar with the matter.

The restriction is aimed at closing a crucial loophole in the export controls the US implemented in October that allowed Chinese AI firms to access high-end chips through the cloud.

The US Department of Commerce is likely to implement the restriction in coming weeks as part of an expansion of last year’s chip control rules aimed at hobbling China’s semiconductor industry.

In March, the Financial Times reported that Chinese AI companies, including those sanctioned by the US, were able to access advanced chips like Nvidia’s A100 for $10 an hour through cloud computing providers. Such use was not a violation of current US rules.

An executive from an unnamed US tech giant in China told the FT that the company had been providing local companies A100 chips-based cloud computing services after it determined that such a move did not violate US sanctions.

“A large number” of Chinese start-ups had been using the service to clone ChatGPT, the executive said.

A restriction on such services would be the latest shot by the Biden Administration in an ongoing tech war with China, which has seen Beijing implement multiple tit-for-tat bans, including one on exports of crucial chipmaking materials announced today.

Beijing said on Monday that exporters would now need permission to ship more than a dozen gallium and germanium products widely used in the semiconductor industry.

It said the controls on the metals aimed to protect national security and China’s interests.

Japan and Europe, both of which have joined the US in implementing chip export curbs, are among the top importers of the metals.

China’s move comes on the heels of top US diplomat Antony Blinken’s trip to Beijing last month and ahead of US Treasury secretary Janet Yellen’s upcoming visit later this week.

Reuters, with additional inputs from Vishakha Saxena