Zohran Mamdani pledged to stand up to pressure from the Trump administration in his first press conference since winning the mayoral race on Tuesday.

The 34-year-old announced his transition team and said he would tackle the "twin crises" of "an authoritarian administration and an affordability crisis".

Trump has referred to the mayor-elect as a communist - a label that Mamdani rejects, and has implied the administration would withhold federal funding from New York City if he won.

The president hinted at a new political rivalry on Election Night, posting "AND SO IT BEGINS!" on his Truth Social account shortly after Mamdani won.

In an interview with Fox News on Wednesday, Trump said that Mamdani had a "pretty open shot" in the race due to lacklustre opponents. The president said he is "torn" about the win and blasted Mamdani's victory speech, characterising the mayor-elect as "very angry" toward him and saying he is "off to a bad start".

"He has to be a little bit respectful of Washington, because if he's not, he doesn't have a chance of succeeding," Trump said. "And I want to make him succeed. I want to make the city succeed. I don't want to make him succeed. I want to make the city succeed."

Trump has referred to Mamdani as "extreme," and Republican House Speaker Mike Johnson has said his party will tie Democrats to Mamdani's policies in next years' midterm elections.

Mamdani is a self-ascribed democratic socialist. It has no clear definition but essentially means giving a voice to workers, not corporations. Mamdani has promised to tax millionaires to pay for expanded social programmes.

"I hope it works out for New York," Trump said of Mamdani on Wednesday. "We'll help him a little bit, maybe."

In his election night speech, Mamdani addressed Trump directly, telling him to "turn the volume up" on his television to hear the enthusiasm of his supporters.

He again spoke of the president in his remarks on Wednesday, saying he would not "mince my words" when it comes to Trump. But he also acknowledged he would always leave a "door open" to have conversations with the Trump administration to discuss his priorities, such as bringing down the cost of living.

In both his victory speech and his first press conference, Mamdani spoke at length of his plans to deliver on signature campaign promises like free buses and freezing the cost of rent-stabilised apartments.

Mamdani named several members of his transition team: Lina Khan, the former Federal Trade Commission chair; Elana Leopold, who worked for former New York City mayor Bill de Blasio; and Maria Torres-Springer, a former deputy mayor in the outgoing Eric Adams administration.

They will be tasked with helping Mamdani assemble his administration ahead of his 1 January 2026 inauguration.

Mamdani also confirmed that he would keep Jessica Tisch as New York City Police Department commissioner, after facing questions about his public safety agenda throughout the campaign.

"It will be my job to stand up for the city and also to ensure that we do not look at Washington DC as if it is the reason for all of the problems right here in New York City," Mamdani said.

The dynamic with Trump will likely hover over Mamdani's transition and the early months of his administration. He will be sworn in as mayor on 1 January. Mamdani will also likely have to navigate Trump's ongoing immigration enforcement operations in the city.

"I think his threats are inevitable," Mamdani said in an interview with ABC News on Wednesday.

"I'm looking forward to showing the power of an example here in New York City, an example of what it means to not just diagnose the despair in working people's lives as the cost of living crisis, but to deliver on it," Mamdani said. "And that's the contrast between myself and President Trump."