US President Donald Trump has thrown his support behind Andrew Cuomo in the New York City mayoral race, warning voters against choosing progressive front-runner Zohran Mamdani.

On Monday evening, Trump posted on Truth Social: "Whether you personally like Andrew Cuomo or not, you really have no choice. You must vote for him, and hope he does a fantastic job. He is capable of it, Mamdani is not!"

The president also suggested he would restrict federal funding for New York City if Mamdani were elected, saying he would provide only “the very minimum” of financial assistance to his hometown under those circumstances.

In a Sunday interview with CBS’s 60 Minutes, Trump doubled down on his stance, calling Mamdani a communist, an accusation the Democratic nominee has repeatedly denied. "It's gonna be hard for me as the president to give a lot of money to New York," Trump said. "Because if you have a communist running New York, all you're doing is wasting the money you're sending there."

Mamdani quickly pushed back, saying he would "address that threat for what it is: it is a threat. It is not the law." The 34-year-old state assemblyman identifies as a democratic socialist and has dismissed the “communist” label, joking in one interview that he was "kind of like a Scandinavian politician," only browner.

Trump’s comments are consistent with his administration’s history of reducing or attempting to cut funding to Democratic-led regions. This fiscal year, New York City received $7.4 billion (£5.7bn) in federal funding.

Cuomo, running as an Independent after losing the Democratic primary to Mamdani, responded to Trump’s statement with caution. "He's not endorsing me. He's opposing Mamdani," the former New York governor said. Cuomo has been a long-time critic of Trump but acknowledged that the president’s remarks might help him indirectly.

Despite Trump’s backing, Cuomo faces an uphill battle. Polls show Mamdani, the Democratic nominee, leading the race, while Republican Curtis Sliwa trails behind. Trump notably declined to support Sliwa, instead posting: "A vote for Curtis Sliwa ... is a vote for Mamdani."

Mamdani countered that "the MAGA movement's embrace of Andrew Cuomo is reflective of Donald Trump's understanding that this would be the best mayor for him." He continued, "Not the best mayor for New York City, not the best mayor for New Yorkers, but the best mayor for Donald Trump and his administration."

During the 60 Minutes interview, Trump compared Mamdani unfavorably to former Mayor Bill de Blasio, saying his leadership would make de Blasio “look great.” He added, "I got to see de Blasio, how bad a mayor he was, and this man will do a worse job than de Blasio by far."

The president, who grew up in Queens and still owns property in New York, also said: "I'm not a fan of Cuomo one way or the other, but if it's gonna be between a bad Democrat and a communist, I'm gonna pick the bad Democrat all the time, to be honest with you."

If elected, Mamdani would become New York City’s first Muslim mayor and its youngest in over a century. He has accused Cuomo of being Trump’s political “puppet,” saying on Monday: "The answer to a Donald Trump presidency is not to create its mirror image here in City Hall. It is to create an alternative that can speak to what New Yorkers are so desperate to see in their own city and what they find in themselves and their neighbours every day - a city that believes in the dignity of everyone who calls this place home."

Cuomo, meanwhile, has positioned himself as the only contender with the experience to manage tensions with the Trump administration. As governor during the Covid-19 pandemic, he frequently clashed with Washington though his handling of nursing home deaths drew heavy criticism after investigations revealed underreported fatalities.

"I fought Donald Trump," Cuomo declared in a recent debate. "When I'm fighting for New York, I am not going to stop."

Trump’s administration has previously deployed National Guard troops to Democratic-led cities as part of its anti-crime measures and has sought to withdraw funds from jurisdictions limiting cooperation with federal immigration enforcement.