Zohran Mamdani sworn in as mayor of New York City

Just moments after the clock struck midnight, Democratic politician Zohran Mamdani was sworn in as Mayor, becoming the first Muslim to lead the Big Apple.

Mr Mamdani beat back a challenge from Andrew Cuomo to be elected last year, promising he would be "a mayor who can stand up to Donald Trump and actually deliver".

He declared during one primary debate that "I am Donald Trump's worst nightmare", adding, "as a progressive Muslim immigrant who actually fights for the things that I believe in".

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Mr Mamdani energised young voters and immigrant communities by promising greater investment in social services and public transport, including free buses across the city.

“This is truly the honor and the privilege of a lifetime,” Mr Mamdani said on New Year’s Eve.

“I cannot wait to see everyone tomorrow as we begin our term.

“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, the health, the legacy of our city.”

Due to his Muslim faith, Mr Mamdani was sworn in using a Qur’an, becoming the first New York City Mayor to do so.

Last night’s ceremony will be followed by an address on New Year’s Day, with Mr Mamdani expected to be joined by Bronx Democratic congresswoman Alexandria Ocasio-Cortez and sworn in by Vermont senator Bernie Sanders.

“When 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,” Mamdani said in a statement.

“That ambition need not be a memory confined only to our past.”