"Even with the Security Council's resolution adopted on other sanctions, the door is still open for a negotiated settlement," Secretary-General Ban Ki-moon told reporters.
Ban was responding to a question about Iranian President Mahmoud Ahmadinejad's announcement that Iran is ready to resume talks on its nuclear program but wants to delay them for several weeks to punish the West for imposing new sanctions.
Ahmadinejad said Iran would be prepared to return to talks only by the second half of the Muslim festival of Ramadan — in late August. "It's a punishment to teach them a lesson to know how to have a dialogue with nations," he said
Ban said he discussed Iran with top European Union officials on the sidelines of the summit of leaders of the Group of 20 club of big developed and developing nations in Canada. He called for Iran and the five permanent UN Security Council members and Germany to resume negotiations.
"I will continue to urge the leaders of the world, the concerned parties to continue their negotiations for an eventual resolution of this issue," he said.
Earlier this month the Security Council passed a fourth round of sanctions against Tehran over a nuclear program that countries around the world increasingly suspect is aimed at producing arms. Tehran rejects the allegations and says its atomic ambitions are limited to generating electricity.
The new UN sanctions against Iran, which received the backing of Tehran's traditional supporters Russia and China, were followed by new rounds of tougher EU and US measures.
n his first news conference since the US Congress approved new sanctions, Ahmadinejad dismissed the CIA's assertion that Iran has enough nuclear material for two bombs if further enriched.
"Are they so afraid of two bombs? There are 20,000 bombs stockpiled and they are so afraid of the possibility of the existence of two bombs? This is really amazing," he said.
"We have said that atomic bombs belong to governments which are politically retarded, those who lack logic. What is the use of those bombs?"
Iran maintains its uranium enrichment is for purely peaceful purposes like electricity and medicine.
Tehran has held no substantive talks with the West since October, when it backed away from a deal to send some of its low-enriched uranium abroad in exchange for the higher-enriched material it needs to fuel a medical research reactor.
In February it announced it had started enriching to that 20 percent level itself — alarming those countries that fear the Islamic republc aims to make even purer, weapons grade material.
Ahmadinejad said Iran still wanted to do a fuel swap, based on a deal agreed in May with Turkey and Brazil which proved too little too late to fend off a new wave of sanctions.
"We preferred and we still prefer to get the 20 percent enriched fuel, to purchase it from the market," he said.
Whether Tehran is prepared to relinquish enough low-enriched uranium to reassure its critics would be key in any future talks. Western diplomats say the amounts agreed in October are no longer relevant as Iran has stockpiled much more since then.
Ahmadinejad said the amount of fuel included in a swap would "depend on our requirements." "We don't know why they insist so much on 'whatever you produce, give it to us'," he added.
He called on the major powers to "clarify" three things before talks could resume: their attitude to Israel's alleged nuclear arsenal, their stance on global nuclear disarmament and whether they come to the table as Iran's friend or its enemy.
Iran would be prepared to return to talks no earlier than the second half of the Muslim festival of Ramadan — in late August, he said, calling this a delay to "punish" the West.
"Independent countries" that believe in "justice and respect" should join any future talks, he said — possibly a reference to Turkey and Brazil which voted against UN sanctions.
The hard-line president also warned that any inspections of its ships related to sanctions could provoke retaliation.
"If they make the slightest mistake we will definitely retaliate," Ahmadinejad said, without elaborating.
