Speaking within hours of each other, Mr Abbas warned against allowing “another Nakba” and called for faster implementation of the US-led peace plan for Gaza. Mr Netanyahu used his time at the podium to defend Israel's military campaign and its settlers in the West Bank, and to attack critics he said were fomenting anti-Semitism.

Mr Abbas addressed the chamber in a recorded video from Ramallah after the US denied visas to him and other Palestinian officials, saying they had failed to meet their peace-process commitments.

He accused Israeli forces of killing, destruction, starvation and attempts to displace Palestinians in the Gaza Strip, saying the conflict had created an unprecedented humanitarian catastrophe.

“Do not allow terrorist gangs protected by the Israeli occupation forces to burn Palestinian homes while their occupants are sleeping inside them,” Mr Abbas said. “Do not allow our children to live afraid and threatened.”

Mr Netanyahu dismissed violent settlers in the occupied West Bank as “juvenile delinquents”, and accused western media of focusing on a small number of Israelis while overlooking Palestinian attacks.

“What they cover is a handful of young juvenile delinquents, about 150 in number,” he told the UN General Assembly. He had ordered investigations into settler violence, he added.

He said such attacks paled in comparison with “thousands of terrorist attacks” against “peaceful settlers”.

Shortly before Mr Netanyahu spoke, delegates from dozens of countries walked out of the UN chamber. Boos and cheers could be heard in the hall.

Protests were also held outside the UN headquarters against Mr Netanyahu, and a billboard under a bridge called him a “war criminal”, in reference to the arrest warrant issued against him by the International Criminal Court.

Mr Netanyahu is seeking re-election in Israel’s October 27 polls, with recent surveys showing a tight race.

Gaza peace

Mr Abbas said that, nearly a year after the establishment of US President Donald Trump's Board of Peace, the next stage of the Gaza peace plan had yet to be implemented.

“We call for accelerating the implementation of the second phase rather than wasting any more time,” he said. The transitional period, which is due to end in 2027, “must not be allowed to become a permanent or open-ended situation”, he added.

Gaza's Health Ministry says 73,928 Palestinians have been killed in the territory since October 7, 2023, when a Hamas-led attack on southern Israel killed 1,200 people.

Mr Netanyahu rejected allegations that Israel is committing genocide, calling them the "greatest lie of the century."

"We've taken innumerable steps to protect the civilian population. Is this genocide? Of course not. It's the opposite of genocide," he said.

He also criticised New York Mayor Zohran Mamdani and accused him of allowing anti-Semitism to flourish in the city.

“Since you were elected Mayor of this city, many Jews no longer feel safe in New York,” Mr Netanyahu said, and that Mr Mamdani was associating with people he described as supporters of Hamas.

“You count as friends people like Hassan Piker, who said America deserved 9/11,” he said. “Some friends you have.”

He also referred to social-media posts liked by Mr Mamdani’s wife, which he said praised the October 7 attacks

Mr Mamdani is a fierce critic of Mr Netanyahu and had sought to have him arrested on an ICC warrant while he visited New York.

Mr Netanyahu also described Turkish President Recep Tayyip Erdogan as a "tyrant" who wants to take over Syria.

In his UN address, Syrian President Ahmad Al Shara called for Israeli withdrawal from parts of the Golan Heights occupied since the fall of the regime of Bashar Al Assad.

Mr Netanyahu told Mr Al Shara in his address that Jews had been in the Golan Heights “since the days of Moses”.

He also said Israel had inflicted major blows on Iran, Hamas and Hezbollah, crediting the US with helping to attack Iranian military and nuclear sites.

“With our great American friends, we crushed Iran's army, navy, air force, and nuclear facilities,” Mr Netanyahu said.

At one point, he held up a Starlink satellite receiver, saying he would leave it in New York for Iranian diplomats to use when they "inevitably defect".

“The Iranian regime is especially afraid when their people have this … communications device, Starlink,” he said, accusing Tehran of spending billions to censor the internet.

West Bank

Mr Abbas accused Israel of accelerating settlement expansion in the occupied West Bank, including East Jerusalem, and said settler violence was increasing under the protection of Israeli forces. He also spoke of land confiscation, home demolitions, checkpoints and raids.

“We warn you today: do not allow another Nakba to occur,” Mr Abbas said, referring to the forced mass ejection of Palestinians from their homes during the 1948 war. “Do not allow further massacres like those that occurred in 1948.”

He said Israeli policies, including the proposed E1 settlement, threatened “the very life and existence of the Palestinian people on their homeland”.

He called on the international community to protect Palestinians, ensure their continued presence on their land, end the Israeli occupation and implement a two-state solution based on international resolutions.

He also questioned why some countries continued to remain silent or supply Israel with weapons, saying the international community had witnessed the “tremendous cost” of the conflict in Gaza and the West Bank.

Mr Abbas accused Israeli “extremism” of seeking to expand a colonial project towards establishing “Greater Israel” and “completely erasing Palestinian presence”.

He urged the US administration to “return to dialogue and mutual respect” and work with the Palestinians and the international community to implement a two-state solution based on international legitimacy.

– Thomas Watkins contributed to this report from Washington. Amr Mostafa reported from Abu Dhabi.