Billionaire investor George Soros ripped Facebook CEO Mark Zuckerberg in a letter to the Financial Times, suggesting the tech exec is engaged in a quid pro quo with President Trump. Soros, who is well known for donating to liberal causes, also called for Zuckerberg and Sheryl Sandberg, Facebook’s chief operating officer, to be “removed” from controlling the company.

“Mr. Zuckerberg appears to be engaged in some kind of mutual assistance arrangement with Donald Trump that will help get him to get re-elected,” Soros wrote in his letter to FT, published Monday.

Soros did not expand on his claim, but it comes a month after the president said Zuckerberg, during a recent dinner, told Trump he was “number one on Facebook.” Trump’s campaign ran a well-crafted Facebook ad strategy during the 2016 presidential election — something Facebook employees later said was “more complex” than Hillary Clinton’s digital efforts.

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