The Japanese government plans to implement strict controls on foreign investment in companies involved in the coronavirus treatment Avigan, the Yomiuri newspaper reported.

The move would be an extension of revised rules on foreign ownership in companies deemed critical to national security. The Ministry of Finance released a list of 518 such companies on Friday.

Japan's Fujifilm Holdings Corp is working with domestic suppliers to ramp up production of its anti-flu drug Avigan that is being tested as a treatment for COVID-19.

Chemical makers Denka Co and Kaneka Corp are among Avigan raw materials suppliers that would be subject to the revised ownership rules, Yomiuri said.

(Reporting by Rocky Swift; Editing by Kim COghill)