An IAEA team of judicial experts is expected in Iran early this week on a 48-hour mission to explain how the additional protocol to the Nuclear Non-Proliferation Treaty (NPT) works, the Vienna-based agency said.
A second team is also expected for routine inspections ahead of the release of an IAEA report on Iran's nuclear facilities on September 8, it added, without giving specific dates for the visits.
Iran, pressured by the United States as well as those it considers partners, Russia and the European Union, to sign up to the additional protocol of the NPT, requested the first visit to seek legal clarifications.
"After these people come to Iran and we listen to their reasons and justifications, then we will decide whether to sign the IAEA's additional protocol," Foreign Minister Kamal Kharazi said on July 29.
In Iran, the concern voiced by the international community that Tehran's declared nuclear energy program could be a cover for developing nuclear weapons has raised a heated debate on how Tehran should respond.
Some officials have argued Tehran should sign the protocol, which would allow international inspections of installations without prior notice, while others insist signing would threaten Iran's independence and sovereignty.
Iran's IAEA representative Ali Akbar Salehi advised his government, in a newspaper interview published in late July, to sign up to the protocol in the coming month.
"We are currently in a situation in which the protocol can help us settle some problems and close the political file opened on our nuclear activities," he said.
Salehi argued this would help lift the international pressure on Iran, as well as the risk that the IAEA could decide at its September board of governors meeting to refer Iran's case to the UN Security Council.
But for Hossein Shariatmadari, chief editor of conservative daily Kayhan, signing the protocol means allowing inspectors "in the service of America, Israel and the European Union" to interfere with Iran's strategic interests.
"The conspiracy of the Americans and their allies, as well as of the United Nations, against the Islamic Republic leaves us no choice but to pull out of the NPT," he said.
In response to pressure, Iran has toned down its insistence that Western states assist it in developing its civilian nuclear program, which it says the NPT requires them to do.
It has also not ruled out the option of signing the additional protocol.
Clearly, the stakes are high as the European Union on July 21 expressed its "increasing concern" over Iran's nuclear program and demanded "unconditional" acceptance of the protocol.
The union, which is negotiating a key trade pact with Iran, said it would review its cooperation with Tehran after an IAEA report due in September on Iran's nuclear program.
The United States has also been trying to persuade Russia to stop helping Iran build its first nuclear power plant near the southern city of Bushehr.