Iran and the International Atomic Energy Agency (IAEA) Friday resumed talks in Vienna, hoping to sort out the differences on conducting investigation into the alleged nuclear weapon program in the Islamic republic.

IAEA chief inspector Herman Nackaerts and deputy director general Rafael Grossi are holding the talks with Iran's envoy to the agency, Ali Asghar Soltanieh.

In the meeting, the IAEA is expected to push for probing the activities in the Parchin military complex near Tehran. Iran has so far indicated that it will limit the scope of the investigation to be conducted by the IAEA.

The U.S. and other Western nations have charged that Iran is in the process of building a nuclear weapon, a claim which Tehran has denied. The U.S. and Europe have tightened economic sanctions against Iran. Tehran has repeatedly argued that such sanctions will neither cripple the country's economy nor disrupt its nuclear research program.

Iran has threatened to withhold oil deliveries and block the Strait of Hormuz, through which a fifth of the world's oil flows. Iran's top oil buyers in Europe have made substantial cuts in imports ahead of the European Union sanctions, which will come into effect in July.