Alchip, which said 39 per cent of its revenue last year came from Phytium, added that it was collecting "detailed documents for our U.S. counsel to determine if the products are subject to EAR (Export Administration Regulations)".

A U.S. Bureau of Industry and Security "permit will be obtained for Phytium's products if necessary", it added.

Its share price tumbled 9.9 per cent on Wednesday, bringing losses to more than a third of the shares' value since the Commerce Department's announcement last week.

Separately, Hong Kong's South China Morning Post reported that Taiwan Semiconductor Manufacturing Company Co Ltd (TSMC) , the world's largest contract chipmaker, has suspended new orders from Phytium.

TSMC said it could not confirm the report, and declined further comment.

TSMC shares closed up 1.16 per cent on Wednesday, outperforming a 0.24 per cent rise in the broader Taiwanese stock market.

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