Delegations from Iran and the U.N. International Atomic Energy Agency have held a second day of talks in Tehran to try to resolve questions about Iran's nuclear program, including its use of advanced centrifuges.
IAEA Deputy Director General Olli Heinonen and Tehran's deputy nuclear negotiator, Javad Vaeedi, led Wednesday's meeting.
An Iranian news agency (Fars) reports the talks will continue on Thursday, and that the results will be announced late this month.
The meetings are focusing on Iran's plans to develop advanced centrifuges that enrich uranium more efficiently than Tehran's existing technology.
Iran and the IAEA agreed in August on a timetable for Tehran to answer all remaining questions about its nuclear program by December. The agreement does not require Iran to suspend the current expansion of its uranium enrichment facilities.
Iranian state media (IRNA) say the resolution of questions about Iran's centrifuges will allow the two sides to address the issue of contamination found by U.N. inspectors at Iranian nuclear sites.
The United States and its allies accuse Iran of seeking to build atomic weapons under the cover of a civilian nuclear program. Iran denies the charge.