IAEA detects new activity at Iran’s Jabal Al-Fas nuclear site

The International Atomic Energy Agency has detected construction and activity at Iran’s Jabal Al-Fas site, located south of the main Natanz uranium enrichment facility, as inspectors remain unable to access the fortified tunnel complex inside the mountain.

In an interview with Bloomberg on Thursday, IAEA Director General Rafael Mariano Grossi said satellite images showed signs of movement and new work at the site, noting that there were "some indications of activity around the construction area."

Grossi emphasized that the agency does not have confirmed information about the nature of the activities taking place inside the site.

Jabal Al-Fas is located about 220 kilometers south of Tehran and is considered a highly fortified facility suspected of links to nuclear activities. Construction is believed to have started after an Iranian centrifuge production facility was targeted in a sabotage attack about six years ago.

Grossi explained that at the time, Iranian authorities announced plans to move some activities into tunnels and mountains to protect them from attacks.

These developments come after the IAEA Board of Governors referred Iran’s nuclear file to the UN Security Council, citing Tehran’s failure to comply with requirements related to its nuclear activities.

Since June 2025, the agency has faced difficulties verifying the status and location of Iran’s stockpile of uranium enriched to near weapons-grade levels, following Israeli and US attacks on Iranian nuclear facilities.

Former US President Donald Trump also referenced activity at Jabal Al-Fas last week, warning Iran against what he described as troubling moves. Speaking at a Republican campaign rally on Wednesday, Trump said there was "minor activity" at the site, advising Iran "not to mess around" and warning that the US "would have to hit them very hard" if such activities continued.

The IAEA Board’s decision to censure Iran has raised concerns it could pave the way for new military strikes on its nuclear facilities, as Trump continues to stress that preventing Tehran from developing a nuclear weapon is a key reason for confronting Iran.

In response, Tehran has warned Western countries against turning the IAEA into a "tool of war." Iran’s envoy to the agency said in a diplomatic note circulated this week that the Israeli and US attacks in June 2025 occurred just hours after the nuclear decision was issued, calling it evidence of a "hidden agenda" among supporters of the resolution.