The European Union says Twitter is pulling out of the EU's voluntary code of practice against disinformation.
However, EU internal market commissioner Thierry Breton warned the social media giant, "you can run but you can't hide", with new laws targeting disinformation coming into effect on August 25.
Twitter has not confirmed it will leave the voluntary code, and was still listed among signatories when Mr Breton made his comments.
Since taking the reins last year, Twitter CEO Elon Musk has reinstated accounts previously banned for spreading misinformation; slashed moderation teams and rolled back its COVID-19 misinformation policy.
The EU's Strengthened Code of Practice on Disinformation was expanded last year, building on the initial code introduced in 2018.
It requires signatories to commit to measures such as demonetising the spread of disinformation; guaranteeing transparency of political advertising; enhancing cooperation with fact-checkers; and facilitating researchers' access to data.
Signatories include Google, Meta and TikTok, among groups from the advertising industry, fact-checkers, and organisations with specific expertise on disinformation.
However, obligations to combat disinformation will be beefed up in August with the EU's Digital Services Act.
Last year, Mr Breton warned Mr Musk that Twitter needed to beef up its measures to protect users from harmful content, to avoid violating the new rules, which threaten tech giants with big fines or even a ban.
EU 'ready for enforcement'
In a tweet, Mr Breton warned Twitter that "obligations remain", even if the platform withdraws from the voluntary code.
"You can run but you can’t hide," he said.
"Beyond voluntary commitments, fighting disinformation will be legal obligation under #DSA as of August 25.
"Our teams will be ready for enforcement."
