President Trump hosted Facebook CEO Mark Zuckerberg and board member Peter Thiel at a White House dinner in October that was not disclosed, the social network giant confirmed to NBC late Wednesday.

Details: NBC notes that it's "unclear why the meeting was not made public or what Trump, Zuckerberg and Thiel discussed."

What they're saying: A Facebook spokesperson told the network, "As is normal for a CEO of a major U.S. company, Mark accepted an invitation to have dinner with the President and First Lady at the White House."

The big picture: Trump also had an unannounced meeting with Zuckerberg in September. The meetings took place as Zuckerberg faced pressure from regulators and lawmakers on privacy and other issues.

Billionaire investor Thiel is the tech industry's highest-profile Trump supporter.

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