The head of the UN nuclear watchdog on Wednesday indicated that inspectors would eventually gain access to Iranian uranium enrichment sites, a crucial element of the interim agreement between the United States and Iran aimed at ending the conflict.
International Atomic Energy Agency (IAEA) Director General Rafael Mariano Grossi made the clearest statement so far from the UN agency, which plays a central role in assessing the status of Iran’s nuclear stockpile.
Access to enrichment sites
Since Israel’s 12-day war with Iran in 2025, Tehran has barred IAEA inspectors from visiting enrichment facilities where the Islamic Republic is believed to hold enough highly enriched uranium to potentially produce up to 10 nuclear weapons if it decided to pursue one. Iran has consistently maintained that its nuclear programme is peaceful, despite being the only country enriching uranium to 60% purity without a weapons programme.
The US and Iran offered conflicting statements on Tuesday over whether inspections of those sites would take place. Grossi described the situation as a “war of words”.
“I can understand political statements, they are part of the reality, but the fundamental thing I would like to remind you and draw your attention to is that there has been a Memorandum of Understanding, signed by both presidents,” he said at a news conference at the tsunami-hit Fukushima Daiichi nuclear power plant.
Grossi cites terms of agreement
The agreement, Grossi said, “says explicitly that the nuclear activities that are going to be carried out with regards to the nuclear material facilities will be supervised by the IAEA -- in all letters.”
He added, “Obviously, to do that, we will have to inspect. Whether this happens the day after tomorrow or in one week or in 10 days, it's important, but not essential. This is going to happen.”
The inspections are considered vital to the deal, which requires Iran’s stockpile of highly enriched uranium to be downblended.
Iran did not immediately respond to Grossi’s remarks. However, on Tuesday, Foreign Ministry spokesperson Esmail Baghaei said UN inspectors were not scheduled to visit nuclear sites bombed by the US last year, dismissing comments made a day earlier by US Vice President JD Vance.
Concerns over uranium stockpile
While the IAEA has been allowed to visit other Iranian nuclear facilities since the 2025 conflict, including the Bushehr nuclear power plant, it has not been granted access to enrichment sites. As a result, the agency says it cannot verify the status of Iran’s uranium stockpile or inspect the centrifuge cascades used for enrichment. Although both Iran and the IAEA say uranium enrichment activities have ceased, non-proliferation experts remain concerned that Tehran could be moving its stockpile to undeclared locations.
