The United States will seek consensus, rather than a breakthrough, on the issue of Iran's nuclear program as it meets with world powers at the United Nations General Assembly this week.
"The meetings in New York will be an important opportunity for the United States to concert with its partners and be very plain about our shared objectives, what we expect of Iran, and what will define a productive outcome," Susan Rice, US ambassador to the United Nations said last week.
Secretary of State Hillary Clinton will hold talks in New York with her five counterparts from the six nations -- the United States, Britain, France, Germany, China and Russia -- that have for years been negotiating with Iran on its nuclear program.
The high-level nature of the meeting is unusual, and will be complemented by a special session of the Security Council, presided over by US President Barack Obama, devoted to the issue of nuclear proliferation.
Rice said the US leader also would be discussing Iran's nuclear program during bilateral talks with other world leaders in town for the General Assembly.
Among those he will talk with is Group of Eight nations Italy, Canada and Japan, Rice said.
The White House has not said it expects Obama to meet with Iran's President Mahmoud Ahmadinejad, and experts told AFP the US leader was unlikely to directly raise Iran's nuclear program during the Security Council session on proliferation.
Instead, Washington will be looking "to build and sustain as broad a coalition and as strong a coalition as it can on Iran issues," said Jon Alterman, director of the Middle East program at the Center for Strategic and International Studies.
The work done behind the scenes of the General Assembly will better prepare the international negotiating group as it gears up for a meeting between European foreign policy chief Javier Solana and an Iranian counterpart in early October.
But differences remain within the group on the best way to deal with Iran.
Obama continues to pursue an approach that offers the possibility of dialogue, backed with the threat of new sanctions. His approach is supported by Britain, Germany and France, with Paris calling this week for the negotiating group to set a timetable for new sanctions against Iran in case talks fail to yield progress.
But Russia and China are significantly more lukewarm about the strategy of backing negotiations with the threat of sanctions.
Iran, for its part, has said it is ready to talk, but has ruled out in advance shutting down its nuclear program, which it says is intended only to produce civilian nuclear energy.
On Sunday, Iran's supreme leader again rejected claims that his country was seeking
"They falsely accuse the Islamic Republic of producing nuclear weapons," Ayatollah Ali Khamenei said in a speech broadcast by state television.
"We fundamentally reject nuclear weapons and prohibit the production and use of nuclear weapons," he said.
Iran's insistence on ruling out the possibility of suspending its nuclear program is a classic posture for the country to take ahead of major international negotiations, according to several diplomats.
The unrest that followed Ahmadinejad's disputed reelection is also likely to constrain the possibility of any breakthrough in talks, experts said.
"The Iranian regime's behavior during the election and its aftermath limits the political space that one would need to have a dialogue," said Ray Takeyh, a senior fellow at the Council on Foreign Relations.
Facing pressure at home and abroad, Ahmadinejad may be more likely to stick with hardline positions.
He appeared to be taking that approach on Friday, when he once again referred to the Holocaust as a "myth," provoking outraged condemnations from governments and institutions across the world.