Weibo wb , the operator of China’s top microblogging site, will block unapproved video content and work more closely with state media to promote “mainstream” ideas, the firm said, following a sharp rebuke from regulators last week.

Chinese authorities have launched a broad campaign to control political opinion and formalize online surveillance mechanisms, cracking down on online content including literature, livestreaming, news and social media accounts.

Last week, the media watchdog, the State Administration of Press, Publication, Radio, Film and Television, threatened to close Weibo’s video service along with two other popular services, ACFUN and iFeng.

In a statement posted on its website late on Wednesday, Weibo said it “sincerely accepted the criticism”, and would immediately begin work to remove political, media and current affairs video accounts from outlets that lack a license.

Weibo added that it will strengthen cooperation with the country’s top three state media outlets – Xinhua news agency, China Central Television and the People’s Daily – and work to promote outlets that represent mainstream political ideas.

Unlicensed television and film content, as well as videos longer than 15 minutes, will be banned on the platform, it said.

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Television and film producers in China are legally required to submit content for approval, a regulation that has increasingly targeted the country’s extensive and fast-growing online film industry.

China’s cyberspace authorities ordered internet companies earlier this month to close 60 popular celebrity gossip social media accounts to help “actively propagate core socialist values” and prop up “mainstream public opinion”.

Shares in Weibo and Sina sina , which has a stake in Weibo, have fallen since the watchdog issued its warning last week, but are still up nearly 160% over the last year.