Zohran Mamdani was sworn in as New York City mayor in the first minutes of the New Year at the historic City Hall subway station, with his wife Rama Duwaji standing by his side.
The oath, in which he pledged to support the Constitution of the United States and the laws of New York, was administered by New York State Attorney General Letitia James.
"Happy New Year to New Yorkers, both inside this tunnel and above," said Mamdani, standing beneath a vaulted ceiling with the words City Hall over his head. "This is truly an honour and a privilege of a lifetime."
Mamdani was a trailblazing candidate and is expected by many in his city of 8 million -- some with hope, some with trepidation -- to be a disruptive mayor.
The democratic socialist's plans for his first day in office on Thursday nod to his politics and priorities, without straying far from his predecessors with a sober official midnight oath-taking followed by a more celebratory ceremony in the afternoon.
New York law spells out that four-year mayoral terms start on the January 1 after elections. To avoid any ambiguity about who's in charge of America's most populous city, it has become a tradition to hold a small swearing-in just after midnight.
Mamdani chose the Old City Hall subway stop, which was decommissioned in the middle of the previous century and is accessible only a few times a year through guided tours, as the site of his swearing in. The subway site, according to Mamdani’s transition team, reflects his "commitment to the working people who keep our city running every day".
Mamdani, a 34-year-old former state lawmaker, promised a freeze on rents and free buses and childcare, building a campaign around affordability issues that some have seen as a path forward for his Democratic Party around the country ahead of midterm elections.
Mamdani inspired a record-breaking turnout of more than 2 million voters and took 50 per cent, nearly 10 points ahead of Andrew Cuomo running as an independent and well ahead of Republican Curtis Sliwa.
Attorney General James was among his earliest prominent backers. During the first administration of President Donald Trump, James began investigating his business practices in New York, resulting in a judge finding in 2024 that Trump fraudulently overstated his net worth to dupe lenders. The Trump administration has targeted James during his second term, accusing her of mortgage fraud.
Grant Reeher, a Syracuse University political science professor, said James's role in the inauguration would send a message to core supporters that Mamdani is "going to be independent of the president".

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