Deputy Foreign Minister Abbas Araghchi spoke to reporters after meeting with Yukiya Amano, the head of the UN's International Atomic Energy Agency, and shortly before IAEA and Iranian officials sat down to negotiate again about the terms of the IAEA investigation.
Nearly two years of Iran-IAEA meetings have made little progress on terms of an agency investigation into suspicions that Tehran may have worked secretly on nuclear arms. Iran has no such weapons and denies working on them.
Beyond any new Iranian initiative Araghchi's visit had significance on its own. He and other senior Iranian officials have repeatedly expressed willingness to work on reducing fears about Iran's nuclear aims since reformist Iranian President Hassan Rouhani took office in August.
Araghchi was a senior negotiator for Iran at Geneva talks earlier this month with six world powers that are seeking cuts in programmes that Iran says serve only peaceful purposes but which could be re-engineered to make nuclear arms.
While the Vienna and Geneva talks are formally separate, they are linked by concerns over Iran's nuclear aspirations, and progress in one may result in advances in the other.
The Vienna talks have been deadlocked for nearly two years, with agency experts seeking an open-ended probe and Iran insisting that it be carefully scripted with limits on what can be inspected, who can be questioned, and other constraints.
