Iranian nuclear chief Ali Akbar Salehi said the first phase of talks with the UN nuclear watchdog will be finished by early February, English-language Press TV website reported Friday.
Earlier on Friday, Iran and world powers agreed on how to implement a landmark November deal on containing Tehran's nuclear program, but it must still be approved by each country before it can take effect.
Press TV quoted Salehi as saying: "Iran and the agency will end phase one of the negotiations by early February, and the second phase of Iran-IAEA talks will start soon afterwards."
In that second phase, Iran and the International Atomic Energy Agency need to hammer out a clear framework on how to continue their co-operation.
In November, the two sides agreed on a "roadmap for cooperation" to resolve remaining issues linked to Tehran's controversial atomic program.
Under it, Tehran agreed to allow IAEA inspectors to visit the heavy water production plant in Arak as well as the Gachin uranium mine in the south.
The Arak heavy-water reactor, which could be operational by the end of next year, is a major source of concern for Western powers.
Its official function is to produce plutonium for medical research, but it could potentially be used for military purposes.
Western nations and Israel have long suspected Iran of pursuing a nuclear weapons capability alongside its civilian program, charges denied by Tehran.
The IAEA conducts regular inspections of Iran's nuclear facilities but also wants to investigate allegations that Iran conducted nuclear weapons research before 2003 and possibly since then.
Iran allowed the UN atomic watchdog inspectors to visit the Arak site in December, the first time since 2011.
Meanwhile, two days of talks between high-level Iranian and EU negotiators ended in Geneva on Friday with "very good progress on all the pertinent issues," said Michael Mann, a spokesman for EU foreign policy chief Catherine Ashton.
The EU represents the P5+1 group of world powers — Britain, China, France, Germany, Russia and the United States — in the decade-long nuclear negotiations with Iran.
Iran's deputy chief nuclear negotiator, Abbas Araqchi, said "we found solutions for all the points of disagreement."
Under a November deal, Iran agreed to curb parts of its nuclear drive for six months in exchange for receiving modest relief from international sanctions and a promise by Western powers not to impose new measures against its hard-hit economy.