Attorney General Jorge Messias told journalists his office could take "legal and judicial" measures against Meta if it does not respond in time to an extrajudicial notice filed Friday.

Citing "the lack of transparency of this company," Messias said it "will have 72 hours to inform the Brazilian government of its actual policy for Brazil."

Meta founder and CEO Mark Zuckerberg stunned many with his announcement Tuesday that he was pulling the plug on fact-checking at Facebook and Instagram in the United States, citing concerns about political bias and censorship.

The move has raised concerns in multiple countries, including Brazil, that are vulnerable to misinformation.

Meta, which runs the social media platforms Facebook, Instagram and Threads, on Thursday published in Portuguese its new, looser restrictions around topics such as gender and sexual identity.

According to the extrajudicial notice, this allows users to associate sexual identity to "a mental illness or abnormality" and allows "the defense of professional limitations based on gender."

"It is important to remember that Brazil has very strict legislation on the protection of children and adolescents, on the protection of vulnerable populations ... and that we will not allow, under any circumstances, these networks to transform the environment into a digital massacre or barbarity," said Messias.

"Our intention is, in fact, to seek all legal mechanisms within due process and the rule of law so that this company begins to comply with Brazilian legislation."

The extrajudicial notice asks for clarity on how social media algorithms will be designed "in order to unwaveringly promote and protect fundamental rights."

Brazil also wants to know what measures will be adopted to prevent gender-based violence, racism, homophobia, transphobia, suicide, hate speech and other fundamental rights issues.

The country also wants details on how complaints can be filed, and how contradictions and disinformation in the new user-generated "community notes" system will be dealt with.

"The government will not stand idly by, as you can see," said Messias.

AFP currently works in 26 languages with Facebook's fact-checking program, including in the United States and the European Union.

On Wednesday, Brazil's public prosecutor's office sent a letter to local Meta representatives giving the company 30 days to clarify whether it intends to implement the fact-check changes in the country.

Brazil's Supreme Court has taken a strong stance on regulating social media platforms.

Last year, judge Alexandre de Moraes blocked Elon Musk's X platform for 40 days for failing to comply with a series of court orders against online disinformation.