"We had intensive discussions today but did not finalize the structured approach document , "IAEA chief inspector Herman Nackaerts said after meeting Iranian officials in the Austrian capital, Vienna, on Wednesday.

"We will continue to try and complete this process ... And a date for the next meeting is still to be set," the inspector added.

The Islamic Republic and the IAEA opened fresh talks on Wednesday in Vienna to negotiate a technical framework for cooperation.

Iran's Ambassador to the IAEA Ali Asghar Soltanieh heads the Iranian delegation to the talks, while the IAEA delegation is led by Nackaerts, who is also the head of the Agency’s Safeguards Department.

The talks are the 10th round of the negotiations between Iran and the IAEA over the Islamic Republic’s nuclear energy program since early 2012.

The previous round of the negotiations was held in mid-February in Iran’s capital, Tehran.

Meanwhile, Secretary of Iran Supreme National Security Council (SNSC) Saeed Jalili is also in the Turkish city of Istanbul for a meeting with EU foreign policy chief, Catherine Ashton, over the Islamic Republic’s nuclear energy program.