Washington DC - Months of sniping melted away Friday as New York's incoming leftist mayor Zohran Mamdani and President Donald Trump were all smiles at a White House meeting – promising to set aside their feud and cooperate on the city's future.

Mamdani, a 34-year-old political insurgent who rocketed from obscurity to win City Hall earlier this month, had taken on Trump in a bruising war of words, likening the Republican to "bad landlords... taking advantage of their tenants."

Washington watchers were bracing for sparks to fly when the self-described Democratic socialist met the Republican leader who has, in turn, branded the mayor-elect a "communist" and suggested the Ugandan-born New Yorker should be deported.

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But the Oval Office summit was instead the embodiment of civility as a beaming Trump (79) praised Mamdani's historic election win, said he could do a "great job," and called him a "man who really wants to see New York be great again."

"We're going to be helping him to make everybody's dream come true: having a strong and very safe New York," Trump said.

Mamdani described the face-to-face as "very productive" and spoke of the leaders' "shared admiration and love" for America's financial capital and largest city.

Trump repeatedly offered his support for Mamdani – even telling reporters it was "OK" for the younger politician to have called him a "despot."

"I've been called much worse than a despot. So it's not that insulting. Maybe he'll change his mind after we get to working together," a conciliatory Trump said, adding that he hoped Mamdani would be "a really great mayor."

For his part, Mamdani noted that many New Yorkers had backed Trump in the 2024 presidential election "because of that focus on cost of living."

"And I'm looking forward to working together to deliver on that affordability," he said.

It was all a far cry from the barbs the pair had exchanged in the run-up to the meeting.

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Beyond mocking Mamdani's South Asian name, the president has dangled cuts to federal funding and even National Guard deployments – a tactic he used against other Democratic cities.

For New Yorkers, that could mean billions of dollars lost and troops on the streets once Mamdani, set to become the city's first Muslim mayor, takes office.

Mamdani's rise has been nothing short of electric. Virtually unknown a year ago, he stormed the political barricades with a campaign promising rent freezes, free buses, and city-run grocery stores – untested ideas that nevertheless resonated with voters crushed by soaring costs.

He didn't just win – he shattered records, pulling in more than one million votes, the first New York mayoral candidate to do so since 1969.

Yet the firebrand progressive has shown flashes of pragmatism, soothing centrists wary of a radical shake-up.

He reappointed incumbent police commissioner Jessica Tisch, a steady hand popular with rank-and-file officers, and named veteran bureaucrat Dean Fuleihan as his first deputy mayor – signs of continuity amid his promised revolution.

On the campaign trail, Mamdani cast himself as part of the anti-Trump resistance, but he has since stressed his desire to work with the president on the "national crisis of affordability."