Elon Musk’s X was cited as the biggest outlet for peddlers of disinformation as the European Union urged Silicon Valley platforms to step up their vigilance to combat Russia’s “war of ideas.”

European Commission Vice President Vera Jourova said platforms need to act ahead of national and European elections over the next year.

“This is a multi-million euro weapon of mass manipulation aimed both internally at the Russians as well as Europeans and the rest of the world,” Jourova told reporters Tuesday. “The very large platforms must address this risk. Especially that we have to expect that the Kremlin and others will be active before our European elections.”

The EU released reports on how each of the major tech companies, including Meta Platforms Inc.’s Facebook, Alphabet Inc.’s Google and ByteDance Ltd.’s TikTok, are faring in the battle against disinformation.

Most of the major platforms agreed to work with the EU on a voluntary code of conduct, which aims to set industry standards for fact-checking and other measures. The bloc also performed a pilot project to gauge the extent of the problem.

“X, former Twitter, who is not under the code any more, is the platform with the largest ratio of mis- or disinformation posts,” Jourova said. “The pilot also showed that disinformation actors were found to have significantly more followers than their non-disinformation counterparts and tend to have joined the platform more recently than non-disinformation users.”

She noted several steps taken by platforms to combat Russian influence. Google told the bloc that it terminated more than 400 channels involved in Russian influence operations in the first four months of the year. Meta, meanwhile, said it expanded fact-checking partnerships in 22 languages in the EU.

The EU’s new law regulating content on platforms, called the Digital Services Act, went into effect last month.

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“As Twitter has been designated as a very large online platform, of course there are obligations given by hard law,” Jourova said. “So, my message to Twitter is you have to comply with hard law and we are watching what you are doing.”

Jourova also said the influx of Russian disinformation is particularly acute in Slovakia, which holds elections on Saturday.

“Slovakia has been chosen as the country where there is fertile ground for success of the Russian pro-Kremlin, pro-war narratives,” she said, adding that Facebook and Google have taken some steps to augment their efforts to fight fake information after pressure from the EU. “The election this week will be a test case because the approach to Russian war in Ukraine is a divisive line.”

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