The 34-year-old Queens state assemblyman became the first South Asian and Muslim elected to the helm of the largest city in the US

Mamdani was sworn in at the old City Hall subway station by New York Attorney General Letitia James at a private ceremony attended only by his family and close advisers, held around the stroke of midnight as the city ushered in the new year

Hours later on Thursday afternoon, a ceremonial inauguration for Mamdani was held outside City Hall, the seat of New York City government, where Senator Sanders of Vermont administered the oath of office to the 112th Mayor

Thousands of his supporters gathered outside City Hall, filling the streets in freezing temperatures as they cheered the city`s new mayor

On the choice of the old subway station as the venue for his historic swearing-in, the New York Times quoted Mamdani as saying that when the Old City Hall Station first opened in 1904, one of New York`s 28 original subway stations, it was a physical monument to a city that dared to be both beautiful and build great things that would transform working people`s lives

"That ambition need not be a memory confined only to our past, nor must it be isolated only to the tunnels beneath City Hall: it will be the purpose of the administration fortunate enough to serve New Yorkers from the building above"

Mamdani took his oath on a centuries-old Quran from the collections of the Schomburg Centre for Research in Black Culture

Anthony W Marx, President and CEO of The New York Public Library (NYPL), had earlier said that this specific Quran, which Arturo Schomburg preserved for the knowledge and enjoyment of all New Yorkers, "symbolises a greater story of inclusion, representation, and civic-mindedness"

NYPL had termed the selection of the Quran by the incoming administration as highly symbolic, both because of its connection to one of NYC`s most groundbreaking scholars and for its simple, functional qualities