IAEA’s Grossi raises concern over Iran’s lack of transparency on Natanz tunnels

The head of the UN nuclear watchdog voiced concern over Iran’s failure to clarify construction activity near its Natanz nuclear site, where satellite images appear to show a new, deeply buried tunnel next to an older one, along with a newly built security perimeter.

The images were released this week by the Institute for Science and International Security (ISIS), a US think tank, which suggested the site may be part of Iran’s expanding underground nuclear infrastructure.

Rafael Grossi, speaking in Washington after a recent visit to Tehran, said the International Atomic Energy Agency (IAEA) has asked Iran to explain the construction, but has not received a satisfactory response.

“We’re asking them, what is this for? They are telling us, it’s none of your business,” Grossi said on Wednesday, noting Iran’s position is “unique in the world” in not providing prior information on such developments.

While he said it “cannot be excluded” that the site could be used to store undeclared nuclear material, Grossi stressed the agency’s focus is on continued dialogue.

He confirmed that an IAEA technical team will travel to Tehran in the coming days to follow up on his visit and discuss reinstallation of monitoring equipment.

Grossi also commented on renewed diplomatic engagement between Iran and the United States, expressing hope for progress. “There’s a general expectation that this goes well and that the agreement is verified by the IAEA,” he said.