The head of Iran's atomic energy agency has said a US attempt to push for further sanctions against his country will not work, and will only serve to "invalidate" Western powers.
Ali Akbar Salehi, the head of the Atomic Energy Organisation and Iran's vice-president, made the comments on Wednesday after a meeting of government ministers.
He spoke a day after the US said it would submit a resolution at the UN security council for a fourth round of sanctions against Iran for its disputed nuclear programme.
"They [Western countries] invalidate themselves in the view of public opinion by issuing sanctions," Salehi said.
"There are some wise people among them to avoid doing such irrational actions.
"They feel that for the first time in the world, developing countries are able to defend their rights in the world arena without resorting to the major powers and that is very hard for them."
Mojtaba Samareh-Hashemi, a senior adviser to Mahmoud Ahmadinejad, the Iranian president, echoed those remarks on Wednesday, saying the sanctions draft had "no legitimacy at all".
The resolution, if passed, would expand an arms embargo and restrictions against Iran's banking sector and would ban certain overseas activities, such as uranium mining.
Hillary Clinton, the US secretary of state, announced the new sanctions draft on Tuesday, saying it was backed by China and Russia, who have previously resisted calls for new sanctions.
Her announcement came despite a nuclear fuel swap agreement signed on Monday with Iran and non-permanent security council members Brazil and Turkey.
Many believed the deal would blunt the US-led drive for a fourth round of UN penalties on Iran.
The agreement calls for Iran to ship 1,200kg of low-enriched uranium to Turkey, in return for higher-enriched nuclear fuel for a medical research reactor.
Clinton said on Tuesday that Iran was trying to deflect pressure with the fuel swap deal.
Clinton's comments also came despite an appeal from Recep Tayyip Erdogan, the Turkish prime minister, for the international community to support the fuel swap deal.
"I urge the international community to support the final declaration for the sake of world peace," he said in Spain.
"There is a unique chance before us and I believe we should take this chance."
But Clinton said it was not an "accident that Iran agreed" to the fuel swap as the US was preparing to move forward with sanctions.
The US and its allies have said that Iran wants highly enriched uranium to make an atomic weapon, but Tehran says its nuclear programme is simply designed to meet its civilian energy needs.