The New York Times, which ran a long story that put immense pressure upon the director, announces that he has resigned:

The Met said that Mr. Campbell would stay on until June, the end of the fiscal year, but that Daniel H. Weiss, 59, the Met’s president and chief operating officer, would serve as interim chief executive, working with Mr. Campbell and the museum’s leadership work on a transition plan while the museum searches for a successor. “We are not looking to appoint a new director immediately,” said Daniel Brodsky, the museum’s chairman, in a separate letter, “but instead will take some time to consider the leadership needs of the museum in a thoughtful and deliberative way.”

Metropolitan Museum’s Director Resigns Under Pressure  (The New York Times)