Facebook says it will begin manually reviewing advertisements that target certain groups and address politics, religion, ethnicity and social issues.
The company has informed some advertisers about the new "human review" requirement, warning them that it might cause delays before their ads can appear on the social media platform.
Facebook has been criticized in recent months, both for its algorithm that surfaces conspiracy theories and unsubstantiated "news" stories and for advertisements that target users who express racist views.
Most recently, fake and incorrect stories proliferated on Facebook and Google in the wake of the Las Vegas massacre. Some claimed there was a second shooter. Others identified the wrong man — long after police had publicly revealed Stephen Paddock as the gunman — as the attacker.
Before that, Facebook apologized after revelations its automated advertising process was abused to broadcast false news and promote divisive and hateful messages, such as ads aimed at people who've expressed anti-Semitic views.
The company is also under increasing congressional scrutiny after revealing that ads linked to a Russian internet agency were seen by an estimated 10 million people before and after the 2016 election.
Axios first reported on the written notice to advertisers. Facebook confirmed it Saturday.