IAEA Director General Yukiya Amano
IAEA Director General Yukiya AmanoReuters

The head of the UN nuclear watchdog will travel Saturday to Iran for talks on Tehran's nuclear program with senior officials, the International Atomic Energy Agency (IAEA) said in a statement. However, a key covert nuclear site won't be one of his stops.

The discussions between IAEA chief Yukiya Amano and the "high-level" officials will take place on Sunday, the statement said, as a December deadline looms for completion of a long-running investigation into military components of Iran's past nuclear activities.

The IAEA chief was expected to arrive in Tehran in the early hours of Sunday. "The visit will focus on...clarification of past and present outstanding issues regarding Iran's nuclear program," it said.

The UN atomic watchdog on September 9 said Iran must resolve some "ambiguities" over its past nuclear activities before crippling international sanctions can be lifted.

The IAEA wants to probe reports that at least until 2003, Iran's nuclear program had "possible military dimensions" - in other words that it conducted research into making a nuclear weapon.

Iran has claimed that the allegations that it sought to build a bomb - including that it conducted relevant nuclear detonator tests at the covert Parchin military base - are groundless.

However, Iran last October admitted to using Parchin to test exploding bridge wires, used as nuclear detonators.

The IAEA has repeatedly asked for access to Parchin, requests that have constantly been denied. Under a controversial classified side deal with Iran, the IAEA will let the Islamic regime inspect Parchin itself with no international inspectors.

Indeed, Amano's one day visit on Sunday is not to include a tour of Parchin either, despite the key role the site has reportedly played in military aspects of Iran's nuclear program - which is the very issue the IAEA chief is in Iran to explore.

Under the Iran nuclear deal sealed in July between six world powers and Tehran, Iran must reduce in scale its nuclear activities, but it will maintain its entire nuclear program and centrifuges.

As part of the deal, the IAEA will have to verify that Iran does indeed scale down its facilities, clearing a path towards ending UN, US and EU sanctions.

But the nuclear watchdog is also separately tasked with concluding its decade-old investigation into allegations that at least until 2003, Iran's nuclear program had "possible military dimensions."

Iran signed an agreement with the IAEA on the same July day that it signed the nuclear deal with the six powers setting out a roadmap for wrapping up the investigation by December 15.

During his one-day visit, Amano might also appear in Iran's parliamentary panel tasked with reviewing the nuclear deal - the Joint Comprehensive Plan of Action, Iranian media reported on Saturday.

Fars News Agency quoted conservative lawmaker Alireza Zakani, who leads the panel, saying that Amano will go to the parliament at 2 p.m. local time on Sunday.

Iranian lawmakers are in the final steps reviewing the text. It is not clear whether there will be a vote or not.

Earlier this month the Republican-led US House of Representatives rejected the deal on Iran's nuclear program, in a symbolic vote held a day after Democrats in the Senate thwarted a vote there on the deal.

AFP contributed to this report.