Shortly after the U.S. ushered in a new year on Thursday, Zohran Mamdani, took oath of office as the mayor of New York City, becoming the first Muslim and South Asian to hold the office.

New York State attorney-general Letitia James administered the oath as Mr Mamadani placed his hand on a small-sized Quran held by his wife while his parents looked on in admiration.

Mahmood Mamdani, a professor at Columbia University and his wife, Mira, were present at the intimate ceremony held at a decommissioned subway station beneath City Hall. About 20 persons were in attendance. A larger, more elaborate inauguration, expected to draw more attendance, was scheduled for 1 p.m on New Year’s Day.

Mr Mamdani’s assumption of office was occasioned by a smattering of firsts. At 34, he is the youngest mayor elected in the city’s history, the first Muslim to lead New York City and the first mayor sworn in with a Quran.

A Democrat, he wooed New Yorkers with promises to make bus transportation free and childcare affordable, banking on hiking taxes levied on the wealthy.

“This is truly an honour and a privilege of a lifetime,” Mr Mamdani said. “And after just having taken my oath to become the mayor of the city of New York, I do so also here in the old City Hall subway station, a testament to the importance of public transit to the vitality and the health and the legacy of our city.”

Mr Mamdani appointed Michael Flynn the new Department of Transportation Commissioner shortly after assuming office.