Iran says a UN Security Council statement condemning President Mahmoud Ahmadinejad over his call for Israel to be "wiped off the map" is unacceptable.
Mahmoud Ahmadinejad says he speaks for his people
A foreign ministry statement said it was dictated by the Zionist regime that wanted to cover up its own crimes.
The statement also said Tehran respected its UN commitments and had no intention of attacking Israel.
Ahead of the UN session demanded by Israel, President Ahmadinejad stood by his remarks that have caused outrage.
Several countries have protested and UN Secretary General Kofi Annan has made a rare rebuke of Iran.
Israel welcomed the unanimous Security Council statement which said: "The Security Council condemns the remarks about Israel attributed to Mr Mahmoud Ahmadinejad, President of the Islamic Republic of Iran."
In its defiant statement on Saturday, Iran's foreign ministry said: "The declaration published by the Security Council - proposed by the Zionist regime to cover its crimes and give an image at odds with reality - is unacceptable."
It expressed surprise that the Council had never condemned threats made against Iran by the US and Israel or the "crimes" of the Israeli regime.
However, the foreign ministry went on to say Iran was committed to its engagements based on the UN charter.
"It has never used force against a second country or threatened the use of force," it said.
In the context of the international uproar caused by the Iranian president's remarks, this statement is a conciliatory gesture, the first time Iran has indicated it has no intention of attacking Israel, says the BBC's Frances Harrison in Tehran.
Words of the people
Israel's ambassador to the UN, Dan Gillerman, welcomed the condemnation.
But earlier in Tehran, Mr Ahmadinejad said his remarks were "just" - and the criticism did not "have any validity".
Tens of thousands of Iranians attended an anti-Israel rally on Friday
He attended the Jerusalem Day rally in Tehran which Iran organises every year to show solidarity with the Palestinian struggle.
Shouting "Death to Israel, death to the Zionists", the protesters dragged Israeli flags along the ground and set them on fire.
Joining the protest, Mr Ahmadinejad said: "My words were the Iranian nation's words.
"Westerners are free to comment, but their reactions are invalid."
Palestinian chief negotiator Saeb Erekat has distanced the Palestinian leadership from the Iranian position.