Iran’s president Masoud Pezeshkian launched a defiant attack on the United States and Israel at the UN, the day after President Donald Trump threatened to “annihilate” the Islamic Republic.

The US leader warned he could send Iran to “hell” during his combative address to the United Nations General Assembly Tuesday, seven months after the war he started alongside Israel’s Benjamin Netanyahu.

In his address to the gathering in New York on Wednesday, Pezeshkian insisted that Iran would never surrender and held up images of children killed in a strike on a primary school in Minab.

An American delegate walked out of the meeting in response to the comments. The Iranian delegation had done the same during Trump’s comments on Tuesday.

“They have tested the strength and the steadfastness of Iran, and they have learned that Iran cannot be made to surrender,” Pezeshkian said, while praising the country’s “commitment to the negotiating table”.

“They impose the war on us but we have proven that we’re not afraid of fighting, of war, that is defensive in nature, and we will stand in defence of our beloved Iran, our homeland, until our last breath.”

Pezeshkian appeared to touch on the theme of the 81st General Assembly, which has focused on “restoring trust” in the UN, and referred to double standards, accusing the US of having no respect for international law.

“The nuclear weapon is in Israel, but the inspectors in Iran. Israel kills, but Iran is subject to sanctions,” he said. “The US president described us as terrorists. We have been the victims of terrorism.”

The Iranian leader also highlighted the Minab primary school strikes that killed 177 civilians including 120 children and said “children perished under bombs with weapons used by the US and Israel”. A report by the UN recently found that the US was likely responsibly for the attack, in what may have been a war crime.

Pezeshkian said Iran has only operated to protect itself, saying the country “only defended ourselves – we are not terrorists”.

He accused the US of “bullying” and said that the “resistance of the Iranian people will only increase” in the face of sanctions and pressure.

“We will never bow our head or bend at the knee,” he continued. “Iran must be understood by Mr Trump and those who seek to bully us; that we are ready for dialogue and diplomacy and negotiations – without accepting the language of force.”

US secretary of state Marco Rubio later called the Islamic Republic a “malign” force in comments on the sidelines of the meeting on Wednesday.

Earlier in the week Rubio had said that Trump is “open” to dialogue with the Iranians after weeks of stalled talks despite reports that no negotiations had been scheduled.

Trump said on Tuesday that his special envoy Steve Witkoff and son-in-law Jared Kushner had met with Iranian mediators.

“I think there’s a lot of momentum for them to make a deal,” he said after the speech on Tuesday despite its hostile content. “It’s what we’re hearing from everybody.”

Iranian foreign ministry spokesperson Esmail Baghaei said Tehran had engaged with the US through a Qatari mediator and had communicated its conditions including an end to all US “acts of aggression”. They

Diplomatic contact has sparked backlash across Tehran in hardline circles with Iranian sources telling Reuters that the delegation had been ordered not to meet with the Americans face-to-face.

Some Iranian state media initially reported that Iranian foreign minister Abbas Araghchi and Witkoff had met, but Iranian officials told Reuters that this was not face-to-face.

Washington said it will impose secondary sanctions against countries that allow Iranian flights into their territory after Wednesday.

But Iran appeared to threaten neighbours in response with Mohsen Rezaei, secretary of Iran’s Supreme National Security Council, telling state TV that Tehran would ensure neighbouring countries’ airports could not function if they stop Iranian flights.