The United Nations' nuclear watchdog said it and Iran would hold a technical meeting in Tehran on Wednesday, Reuters reported.
Iran and six world powers struck a framework agreement this month to curb Iran's nuclear programme in exchange for easing Western sanctions.
The U.N.'s International Atomic Energy Agency (IAEA) has said it expected progress this month in its own investigation into Iran's current and past nuclear activities.
Diplomats have voiced concern there could be little progress on the IAEA investigation until a final political deal with world powers is reached.