India, Nov. 5 -- New York City's mayor-elect Zohran Mamdani wasted no time taking aim at President Donald Trump on Tuesday night, formally setting the stage for what promises to be one of the most contentious relationships between City Hall and the White House in decades. (Live updates)

"Donald Trump, since I know you're watching, I have four words for you: turn the volume up!" Mamdani declared to a roaring crowd of supporters shortly after being projected the winner. The line, delivered with his signature composure and confidence, was met with thunderous applause - a defining moment that signaled the 34-year-old Democrat's readiness to confront the former New York mogul-turned-president head-on.

The exchange marks the opening salvo in ...