Iran's deputy foreign minister says that Tehran will not ship enriched uranium stockpiles out of the country but is ready to show flexibility on other aspects of its nuclear program.
Abbas Araqchi was speaking on the eve of a two-day meeting in Geneva starting on October 15, the first between Iranian negotiators and world powers since President Hassan Rohani took office in August.
"We will negotiate about the volume, levels, and the methods of enrichment, but shipping out the [enriched] material is a red line for Iran," Araqchi told state media.
Foreign Minister Mohammad Javad Zarif is Iran's top negotiator with the so-called P5+1 group of the United States, Britain, China, France, and Russia plus Germany.
But Araqchi said he will lead the Iranian team in the talks with European Union foreign policy chief Catherine Ashton and representatives from the P5+1 countries.
He said Zarif will attend only the opening meeting.
Rohani's election in June has raised hopes of a negotiated solution to a decade-old dispute over Iran's nuclear program. Western powers suspect the program is aimed at developing nuclear weapons capability, a charge Iran denies.
Iran insists on what it says is its "right" to enrich uranium, a process needed to produce fuel for power stations but which, in a much more advanced stage, could also produce weapons-grade material.
The UN Security Council has demanded that Iran suspend uranium enrichment and has imposed crippling sanctions on the country.
In the last round of talks, in Kazakhstan in April, the P5+1 proposed an easing of sanctions if Iran places limits on its uranium-enrichment program.
U.S. Secretary of State John Kerry is meeting Ashton in London on October 13 for closed-door talks on Iran.
Kerry arrived in London from Kabul, at the end of a 10-day trip around Asia.
Based on reporting by Reuters, AP, and AFP