Twitter is now blocking state-run media outlets from advertising on its platform.

The new policy was announced just hours after the company identified an information operation involving hundreds of accounts linked to China as part of an effort to “sow political discord” around events in Hong Kong after weeks of protests in the region. Over the weekend more than 1 million Hong Kong residents took to the streets to protest what they see as an encroachment by the mainland Chinese government over their rights.

State-funded media enterprises that do not rely on taxpayer dollars for their financing and don’t operate independently of the governments that finance them will no longer be allowed to advertise on the platform, Twitter said in a statement. That leaves a big exception for outlets like the Associated Press, the British Broadcasting Corp., Public Broadcasting Service and National Public Radio, according to reporting from BBC reporter, Dave Lee.

The affected accounts will be able to use Twitter, but can’t access the company’s advertising products, Twitter said in a statement.

“We believe that there is a difference between engaging in conversation with accounts you choose to follow and the content you see from advertisers in your Twitter experience which may be from accounts you’re not currently following. We have policies for both but we have higher standards for our advertisers,” Twitter said in its statement.

The policy applies to news media outlets that are financially or editorially controlled by the state, Twitter said. The company said it will make its policy determinations on the basis of media freedom and independence, including editorial control over articles and video, the financial ownership of the publication, the influence or interference governments may exert over editors, broadcasters and journalists, and political pressure or control over the production and distribution process.

Twitter said the advertising rules wouldn’t apply to entities that are focused on entertainment, sports or travel, but if there’s news in the mix, the company will block advertising access.

Affected outlets have 30 days before they’re removed from Twitter and the company is halting all existing campaigns.

State media has long been a source of disinformation and was cited as part of the Russian campaign to influence the 2016 election. Indeed, Twitter has booted state-financed news organizations before. In October 2017, the company banned Russia Today and Sputnik from advertising on its platform (although a representative from RT claimed that Twitter encouraged it to advertise ahead of the election).