New Delhi, Jan. 2 -- Zohran Mamdani assumed office as mayor of New York City on Thursday (January 1), pledging to wield government power boldly to ease the cost-of-living crisis facing millions of working-class residents.

A Democrat and democratic socialist, Mamdani took office just after midnight at a decommissioned subway station beneath City Hall, placing his hand on a Quran as he was sworn in - making history as the city's first Muslim mayor.

After briefly working from his new office overnight, Mamdani returned to City Hall around midday for a larger public inauguration, where US Sen. Bernie Sanders administered the oath a second time.

"Beginning today, we will govern expansively and audaciously," Mamdani told the crowd. "We may no...