Political upstart Zohran Mamdani secured another key endorsement Wednesday, earning the support of the United Federation of Teachers, New York City’s most powerful teachers’ union, a day after the president of the United States threatened to overtake the five boroughs should the 33-year-old be elected mayor.

President Donald Trump warned that New York won’t ever be the same if New York City mayoral candidate Zohran Mamdani is elected. Mamdani is a Ugandan-born Muslim who won the Democratic Party’s primary for New York City mayor in June and identifies as a Democratic socialist.