Iranian Ambassador to the IAEA Reza Najafi said bilateral talks in Vienna would likely last two days, Iran's state-funded broadcaster Press TV reported Sunday.
"During the negotiations, we will talk about everything, but it is not clear whether agreement would be achieved," he was quoted as saying. "To achieve an agreement, certain conditions should be met."
He provided no details on what sort of conditions Iranian negotiators would lay out for the IAEA.
Yukiya Amano, director general of the IAEA, said in a September report the agency was worried "about possible military dimensions to Iran's nuclear program."
U.N. nuclear inspectors were denied access to the Parchin military complex last year. Amano said inspectors were concerned about the site though Iran said inspectors had failed to convince it a visit to the complex was necessary.
Two days of talks in Geneva ended last week with a joint statement from Iranian Foreign Minister Javad Zarif and European Union foreign policy chief Catherine Ashton describing nuclear negotiations as "substantive."
Iran says it has a right to an enrichment program as a party to the Nuclear Non-Proliferation Treaty. Iran's adversaries say enrichment could take the program down the path toward weaponization.