US President Donald Trump on Monday vowed that Israeli Prime Minister Benjamin Netanyahu would not face arrest at a UN summit in New York, after the city’s new mayor said he was investigating the move.

Mayor Zohran Mamdani admitted he was unsure if he had the power to order police to detain a foreign leader but said he was discussing the matter with his legal team ahead of the UN General Assembly in September.

“Benjamin Netanyahu will not be arrested, in any way, shape, or form, while in the United States of America,” Trump said on social media.

“He is fighting against the Islamic Republic of Iran.”

The Hague-based International Criminal Court said in 2024 that it had reasonable grounds to believe Netanyahu was responsible for alleged war crimes and crimes against humanity related to Israel’s offensive in Gaza following the brutal October 7, 2023 cross-border attack by Hamas.

“I believe that Prime Minister Netanyahu belongs in The Hague,” Mamdani told the New York Times on Saturday, referring to the United Nations’ International Court of Justice (ICJ). “He’s a war criminal.”

“And what you will find is that is an opinion that is held by many, purely because of what his actions have wrought over these last many years.”

However, Mamdani said he was unclear on whether he has the legal authority to order the New York Police Department (NYPD), which he oversees, to detain a foreign leader like Netanyahu.

Therefore, his administration was still mulling whether to arrest Netanyahu if he comes to NYC in September, as expected for the 81st session of the UN General Assembly.

“Whatever the law allows me to do in New York City, that’s what we will do, but we won’t be writing our own laws to that end,” Mamdani added.

During his mayoral campaign in September 2025, Democratic Mamdani had said he would order the NYPD to arrest Netanyahu if he arrives in the city.

Netanyahu’s office also dismissed Mamdani’s stance and said the ICC was a kangaroo court.

According to NYT’s Saturday report, Netanyahu also commented on Mamdani’s threat to arrest him, saying he was not concerned. He went as far as even accusing the mayor of supporting Palestinian resistance movement Hamas.

“I think he should look at who he’s condemning, who he’s praising,” the Israeli premier said during an interview this week with Sid Rosenberg, whom the NYT described as a “frequent critic” of Mamdani.

Mamdani had condemned pro-Hamas chants in January, describing the Palestinian group as a “terrorist organisation” when criticised by some circles.