Zohran Mamdani, who ran for mayor of New York City in part on a promise to stand up to President Trump, will meet with the president at the White House on Friday, weeks before taking office.

Mr. Trump announced the meeting on social media on Wednesday night, saying that Mr. Mamdani had asked for it and labeling him incorrectly as the “Communist Mayor of New York City.” Mr. Mamdani is a democratic socialist.