Shares of Advanced Micro Devices And Intel After Friday sunk The Wall Street Journal reported. China is ordering the country’s biggest telecommunications carriers to stop using foreign chips.

Chinese authorities earlier this year ordered telecom systems to switch to non-Chinese core processors by 2027, the Journal reported, citing people familiar with the matter. The report said the mandate would affect AMD and Intel.

Both stocks were down as much as 4 percent Friday afternoon.

Intel declined to comment on the report. AMD did not immediately respond to a request for comment.

China owns 27 percent of Intel. Income in 2023, making it the company’s largest market. AMD received 15% of sales from China, including Hong Kong. Last year. Their reliance on China underscores the continued importance of the world’s second-largest economy despite U.S. regulations aimed at curbing chip exports to the country and efforts to make China less dependent on foreign technology.

China set new guidelines in December to remove US chips from government computers and servers, blocking processors from AMD and Intel, the Financial Times reported last month.

And in October 2022, the U.S. enacted rules designed to limit China’s access to advanced U.S. chips, particularly important for artificial intelligence technology. Late last year, the US announced new sanctions to prevent further sales of AI chips to China, in an attempt to close perceived loopholes in the previous order.

Bloomberg reported last month that AMD failed to get US approval for an AI chip designed for China and would need to apply for an export license.

Intel has reportedly fended off pressure from AMD to end sales of millions of dollars worth of laptop chips to U.S.-sanctioned Chinese telecom giant Huawei.