"We had a good meeting," said Herman Nackaerts, the chief inspector for the International Atomic Energy Agency, from Vienna. He returned Friday to Austria following a one-day visit to Iran.
Iranian officials Thursday acknowledged inspectors were interested in visiting the Parchin complex near Tehran. In November, IAEA Director General Yukiya Amano said he was concerned that Iran might be hiding nuclear activity from inspectors at the complex.
Nackaerts said "a long day of meetings" resulted in progress on ways to resolve concerns about possibly military aspects to Iran's nuclear program.
"We have not been given access to Parchin this time but as you know access to Parchin is part of the structured approach and we hope as I said that we will implement that shortly after agreeing on the approach," he said Friday.
Ali Ashghar Soltaniyeh, the Iranian envoy to the IAEA, told state-funded broadcaster Press TV that the meetings were "intensive" but "good progress was made."
Both sides agreed to resume negotiations Jan. 16.
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