On Wednesday, western media quoted Nackaerts as saying that the IAEA hoped Iran would allow the inspectors to go to Parchin military site in southeast Tehran, which is a sensitive spot in negotiations between the IAEA and Iran over the latter's contested nuclear program.
Nackaerts on Friday said that he was confident that a deal with Tehran, which includes access to the controversial Parchin base, could be sealed next month.
Speaking upon his return from Tehran, IAEA chief inspector expressed his confidence to finalize a structured approach in the next meeting with Iran in January 2013.
"We were able to make progress on the text of the structured approach to resolving the outstanding issues on possible military dimensions of Iran's nuclear program," Nackaerts said.
"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.
Iranians have stressed that it is not likely for the IAEA officials to visit Iran's military sites unless a modality for investigations is developed between the sides.
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