Soros called these companies “monopolistic,” and accused them of “deliberately engineer[ing] addiction.” Due to their potential for harm, particularly for adolescents, Soros called for their regulation.

Read: Salesforce CEO Marc Benioff Wants to Regulate Facebook Like Cigarettes

“They claim they are merely distributing information,” Soros said. “But the fact that they are near-monopoly distributors makes them public utilities and should subject them to more stringent regulations, aimed at preserving competition, innovation, and fair and open universal access.”

Soros called these companies’ quick rise “unsustainable,” warning that they will likely “compromise themselves” to enter the Chinese market. “There could be an alliance between authoritarian states and these large, data-rich IT monopolies that would bring together nascent systems of corporate surveillance with an already developed system of state-sponsored surveillance,” Soros warned. “This may well result in a web of totalitarian control the likes of which not even Aldous Huxley or George Orwell could have imagined.”

Read: What Is Davos? 4 Things to Know About the World Economic Forum

The billionaire philanthropist proceeded to compare Facebook and Google to mining and oil companies, accusing them of earning their profits “by exploiting their environment.” Social media’s exploitation of the social environment is “particularly nefarious because social media companies influence how people think and behave without them even being aware of it.”

Soros’s warning follows similar remarks made by others at Davos. Salesforce CEO Marc Benioff called for social media to be regulated like the tobacco industry on Tuesday, while British Prime Minister Theresa May on Thursday called for tech companies to do more to protect users, saying they cannot “stand by while their platforms are used to facilitate child abuse, modern slavery, or the spreading of terrorist and extremist content.”