In recent days, there has been a dispute between the US and Iran over the issue of UN nuclear inspectors visiting sites in the country.

On Monday, following talks in Switzerland with Iran’s chief negotiator, US Vice-President JD Vance said Iran had “agreed to invite IAEA inspectors back into their country”.

The next day, Iranian foreign ministry spokesman said there had been “no detailed discussions” and that Iran had no plans to grant IAEA inspectors access to nuclear facilities which were bombed by the US during a 12-day war between Israel and Iran in June 2025.

US President Donald Trump then dismissed Iran’s “protestations and false statements to the contrary”, saying the country had “fully and completely agreed” to inspections.

“There’s a war or words here. Some say ‘yes’, the others say ‘no’,” the IAEA’s chief said on Wednesday. “I can understand political statements. They are part of the reality.

“But the fundamental thing… is that there has been a memorandum of understanding signed by both presidents,” he added. “[It] says explicitly that the nuclear activities that are going to be carried out, with regards to nuclear material, facilities, will be supervised by the IAEA, in bold letters. This is going to happen.”

Grossi said the inspections would take place in collaboration and co-operation with the Iranian government. “Whether this happens the day after tomorrow, or in one week, or in 10 days, it’s important but not essential.”

Iranian Deputy Foreign Minister Kazem Gharibabadi appeared to push back at the comments.

He wrote on X that access to Iran’s damaged nuclear facilities and its nuclear materials would only be addressed within the framework of a final agreement with the US and after practical steps had been taken to lift all sanctions.

“Media noise cannot be used to impose facts on the ground,” he added.

Under the 14-point memorandum of understanding, the US and Iran have committed to negotiating a final deal within 60 days.

It says they have “agreed to resolve the disposition of stockpiled enriched material, pursuant to a mechanism that will be mutually agreed upon… with the minimum methodology to be down-blending on site under the supervision of the IAEA”.

The IAEA said in a recent report, external that its inspectors were allowed to visit Iran’s Bushehr nuclear power plant earlier this month, but that they were still not given access to the sensitive nuclear facilities that were bombed last June.

The watchdog said that meant it could not provide any information on the current size, composition or whereabouts of Iran’s stockpile of enriched uranium, or whether Iran had suspended all enrichment activities. Much of the stockpile is believed to be inside underground tunnels at the Isfahan site.

Enriched uranium can be used to make reactor fuel but also nuclear weapons.

Before the start of the US-Israeli war with Iran on 28 February, the IAEA reported that Iran had 440kg (970 lbs) of uranium that was enriched up to 60% purity, which is near weapons grade. That would theoretically be enough, if enriched to 90%, for as many as 10 bombs.

Iran insists its nuclear activities are entirely peaceful and that it would never seek to develop or acquire nuclear weapons.

Under a 2015 deal with the US and five other world powers, Iran agreed to limit its nuclear activities and allow continuous and robust monitoring by the IAEA’s inspectors in return for relief from crippling economic sanctions.

However, Trump abandoned the agreement during his first term in 2018, saying it did too little to stop a pathway to a bomb, and reinstated US sanctions.

Iran retaliated by increasingly breaching the restrictions of the deal, particularly those relating to uranium enrichment.