Iran agreed on "some points" in talks with experts from the UN atomic watchdog in Tehran on Wednesday, its lead negotiator at the meeting said, quoted by local media.
"Some differences were resolved and agreement on some issues in the modality was reached," Ali Asghar Soltanieh, Iran's envoy to the International Atomic Energy Agency (IAEA), was quoted as saying by ISNA news agency.
"New proposals," Soltanieh said, had been put forward at the talks but they would be discussed at "future meetings".
He did not say if a date had been agreed for the resumption of talks with the IAEA, whose chief inspector Herman Nackaerts was leading its delegation to Tehran.
Nackaerts had hoped that in the meeting, the third of its kind in the past three months, he would "finalise the structured approach document" which would "facilitate the resolution of the outstanding issues related to the possible military dimension of Iran's nuclear programme".
The Vienna-based agency says "overall, credible" evidence exists that until 2003 and possibly since Iran conducted nuclear weapons research.
Iran has consistently rejected the charges, denying the IAEA broader access to sites, scientists and documents involved in these alleged military activities.