Iranian President Mahmoud Ahmadinejad will hold the top position of speakers when the United Nations opens nuclear non-proliferation talks on Monday, dpa reported.
But the United States said Friday it definitely won't be meeting with him during the talks, even though US Secretary of State Hillary Rodham Clinton will attend Monday's opening.
She will be the highest-ranking US diplomat to attend the talks in 10 years.
"Iran knows what our address is - it's the P5-plus-1," quipped the US ambassador to the UN, Susan Rice, at a press briefing. "If Iran has something to say, it knows where to find us."
As the only head of state attending the talks, Ahmadinejad has claimed top billing of individual country speakers at the General Assembly opening.
He is expected to follow opening remarks by UN Secretary General Ban Ki-moon and a representative of the Non-Aligned Movement, for which a nuclear-free world is a major goal.
Clinton is to speak in the afternoon.
Rice was referring to the group that is working towards a fourth round of sanctions against Iran for defying international demands that it stop enriching uranium, a step that could precede nuclear weapons manufacture. The group includes the five permanent members of the Security Council - France, Britain, China, Russia and the US - and Germany, an added party to the talks.
The sanctions' talks are expected to absorb a good bit of the sidelines' talks in New York as more than 180 countries gather to discuss the way forward with the 1968 Nuclear Non-Proliferation Treaty (NPT.)
Iran has sent its Foreign Minister Manouchehr Mottaki around the globe in recent weeks seeking allies to fend off the proposed sanctions.
Rice said that the sanctions' discussions are proceeding at a "significant pace and intensity." China is apparently doing the most foot dragging against the sanctions, insisting on further talks.
"We are working with that sense of urgency. I can't tell you exactly when it will all be cooked," she said.
Ellen Tauscher, under secretary of state for arms control, said the US would be seeking at the NPT talks more authority and money for the UN nuclear watchdog, the International Atomic Energy Agency (IAEA).
"We want a fully-funded IAEA, but one with teeth," she said.
Tauscher also emphasized the "great value" that US President Barack Obama puts on NPT membership. She referred to Obama's recent nuclear posture review, which pledged never to use nuclear weapons first against states that comply with non-proliferation treaties.
The new pledge - a first for the US - leaves open a nuclear strike against countries that have signed on to the global non-proliferation treaty but stand accused of violating its terms.
Obama has told the New York Times that the loophole would apply to "outliers" like Iran, which is an NPT member, and North Korea, which has withdrawn from the treaty while exploding two nuclear devices in past years.