The United States asked South Korea to urge its chipmakers not to fill any market gap in China if Beijing bans memory chipmaker Micron Technology Inc from selling chips, the Financial Times reported on Sunday.

The news comes ahead of South Korean President Yoon Suk Yeol’s visit to the U.S. on Monday for a summit with President Joe Biden.

Yoon’s April 24-29 trip will be the first state visit to the U.S. by a South Korean leader since 2011 and will mark the 70th anniversary of the countries’ alliance.

Washington asked Seoul to encourage Samsung Electronics and SK Hynix to hold back from boosting sales to China if Micron is banned as a result of an investigation by Beijing, the FT added, citing people familiar with the situation.

China’s cyberspace regulator in March said it would conduct a security review of Micron’s products sold in the country. The chipmaker said last month it was cooperating with the Chinese government, and its operations in the country were normal.

The White House did not comment on the FT report, but added that the Biden and Yoon administrations have made efforts to coordinate investments in the semiconductor sector, secure critical technologies, and address economic coercion.

The U.S. has imposed a series of export controls on chipmaking technology to China for fear it could be used to produce chips for military applications. It has blacklisted a number of China’s largest chip firms, including Micron rival Yangtze Memory Technologies Co Ltd.

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