The United Nations' chief nuclear inspector says talks between Iran and the International Atomic Energy Agency (IAEA) are expected to lead to an agreement, next month, on how to conduct an investigation into Iran's controversial nuclear program.
Herman Nackaerts says the IAEA made progress during talks in Tehran and more meetings have been set for January 16.
He commented to reporters in Vienna, on Friday, a day after a seven-member delegation met with Iranian officials. It was the group's the first talks with Tehran since August.
Earlier, Nackaerts said the purpose of the visit was to resolve outstanding issues related to Iran's possible development of nuclear weapons.
Iran says its nuclear program is peaceful.
The United States, on Thursday, imposed sanctions on five Iranian nuclear experts and seven companies for helping Iran move closer towards enriching uranium - essential for building a nuclear bomb.
The new sanctions freeze the U.S. assets of those named and forbids any U.S. citizen or body from doing business with the 12.