Speaking to a U.S. television network, Annan said, "If everybody, all of the stakeholders and the key players, were around the table, I think it would be possible to work out a package that would satisfy the concerns of everybody."
Room For One More
Annan said that talks between Tehran and three key EU countries -- Britain, France, and Germany -- may have broken down partly because of Washington's absence.
He said that fact might have discouraged Iran from becoming fully engaged. "When you are in that sort of mood, given [Iranian] culture, you probably don't put everything on the table," Annan said.
The EU-3 has sought to persuade Tehran to give up nuclear-enrichment-related activities in return for trade incentives and technical help with Iran's commercial nuclear energy program.
However, Iran is widely believed also to be open to the possibility of security guarantees in exchange for giving up its nuclear activities. Such guarantees would have to come from Washington and could not be fully negotiated by the EU states.
There was no immediate response from Washington to Annan's remarks.
U.S. officials have so far focused on raising pressure at the UN Security Council on Iran to give up its uranium-enrichment program.
The U.S. ambassador to the United Nations, John Bolton, said on May 4 that efforts to get a new Security Council resolution are progressing.
"Everybody reaffirmed again that we do not want Iran to acquire nuclear weapons capability," Bolton said following a meeting of representatives of the five permanent members in New York. "Now, there are disagreements, obviously, that we are still discussing, but I think it was a productive discussion, and my own view of how negotiations go is you put the areas of agreement and disagreement out on the table, talk about the principles and theories that are behind your position and then you see if you can resolve them."
Bolton said that success depends on persuading Russia and China to support efforts by the three Western permanent members to make Security Council demands on Iran to stop uranium enrichment legally binding.
The Security Council can do so by applying Chapter 7 of the UN charter, which makes resolutions mandatory under international law.
But as Bolton noted, persuading Russia and China to apply Chapter 7 -- which could also open the way to sanctions against Tehran -- is difficult.
"The critical issue is whether Russia and China will accept a resolution under Chapter 7 that determines that Iran's nuclear program amounts to a threat to international peace and security and decides in a binding fashion under Chapter 7 that Iran has to give up its uranium enrichment, plutonium reprocessing and heavy water [reactor] construction activities," Bolton said.
Both Russia and China oppose any talk of sanctions on Iran, saying the crisis must be solved only through negotiations with Tehran.
Tehran Rejects 'Threat And Intimidation'
Meanwhile, Iran's ambassador to the UN, Javad Zarif, on May 4 called efforts to get a new resolution counterproductive.
"If [the draft resolution] is an attempt to get Iran to agree, it's not a good one," Zarif said. "I think Iran has made it very clear that we are prepared to move forward with transparency measures, Iran is prepared for a negotiated solution, but we always made it also clear that Iran does not respond well to threat and intimidation."
In the past, attempts to get U.S. and Iranian officials together for public talks on any topic have always run aground due to the tensions between the two states.
The United States recently announced it is willing to meet with Iranian officials over Iraq. But Tehran has since signaled it has little interest in such talks.
Iranian President Mahmud Ahmadinjad said on April 24 that "We think that, right now, because of the presence of a permanent government of Iraq, there is no need [for direct meetings]."