SHANGHAI (Reuters) – China’s cyberspace regulator on Tuesday said it would implement rules that require any company with data for more than 1 million users to undergo a security review before listing its shares overseas from Feb. 15.

It also said such firms should apply for cybersecurity reviews before submitting listing appliation to foreign securities regulators. Companies will not be allowed to list abroad if they are found by the reviews to affect national security, it said in a statement on its official WeChat account.

It said in a separate statement it will also implement new rules on algorithm recommendation technology from March 1.

(Reporting by Brenda Goh; Editing by Tom Hogue)