"I will not be welcoming Benjamin Netanyahu or any other war criminals when they come to this city," Mamdani said.
The mayor, on Wednesday, answered questions from reporters after he announced in a video message on Tuesday night that his legal team determined that he does not have the authority to arrest Netanyahu, only the federal government can.
It's an option that President Donald Trump has already declined.
"We're talking about someone who has been charged with crimes against humanity," Mamdani said. "Someone who has visited this city on many occasions and who has been welcomed by previous mayors. I want to make it very clear that that welcome ends with me."
Mayor Mamdani wanted the city to uphold a warrant for Netanyahu's arrest issued nearly two years ago by the International Criminal Court over the war in Gaza. It's a threat Mamdani first announced during his mayoral campaign.
The mayor is now facing backlash from the UJA Federation of New York, the largest Jewish philanthropy organization in the world.
"We ask that the mayor stop his relentless and singular focus on the only Jewish state of Israel and we ask that the mayor do his job, and I think the reason why people elected the mayor was to help bring this city together," said Hindy Poupko, senior vice president of the UJA Federation of New York.
The mayor has condemned the Hamas attacks of October 7, which killed 1,200 Israelis and started the war.
Mamdani has also called the Israeli offensive in Gaza an act of genocide that has killed more than 70,000 Palestinians.
"I have met Palestinian New Yorkers who have told me they have spent decades in this city, saving money to send it back home to build a home in the village they grew up in only to see it obliterated in an instant with an Israeli air strike," Mamdani said.
"We know that demonizing rhetoric against Israel leads to violence against Jews," Poupko said. "So, when you Israel for unique condemnation, unique focus almost an obsession, that indeed endangers Jews everywhere."
The UJA Federation of New York says it will continue to partner with supporters across the state and city to bring together peace among all residents. It's something Mayor Mamdani says he is trying to do too.
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