WASHINGTON—Having denounced several leading news organizations​ as the “enemy of the people,” President Donald Trump on Saturday said he won’t mingle with any members of the press at the annual White House Correspondents’ Association dinner.

Mr. Trump tweeted that he won’t attend the April 29 event, though he didn’t give a reason. “Please wish everyone well and have a great evening!” he wrote. Presidents typically speak at the dinner, a major event on the Washington social calendar.

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