Rafael Mariano Grossi was speaking to reporters in Austria following a briefing to the Government in Vienna.

Israel began launching air and missile strikes against Iranian military and nuclear sites nearly two weeks ago, and the United States carried out surprise bombing raids on three Iranian uranium enrichment facilities this past weekend.

A ceasefire between Iran and Israel, announced on social media by US President Donald Trump on Monday night, is fragile but holding.

However, the extent of damage to Iran’s enriched uranium stockpile remains unclear.

Iran says protective measures taken

Following the initial attacks, Iran informed the IAEA that it would take “special measures” to protect its nuclear materials and equipment.

Mr. Grossi told journalists that he has received a letter from the Iranian Foreign Minister which said protective measures have been taken.

“They did not get into details into what that meant, but clearly that was the implicit meaning of that. So, we can imagine that this material is there,” he said. To confirm this, and to evaluate the situation, “we need to return,” he added.

Inspections vital

On Wednesday, Iran’s parliament approved a bill to suspend cooperation with the IAEA, according to media reports, which has to be approved by the executive branch of the Government.

Mr. Grossi said he wrote to Foreign Minister Abbas Araghchi on Tuesday requesting that they meet “to analyze the modalities” for inspections to continue.

He stressed that the international community “cannot afford” for the inspection regime to be interrupted.

The IAEA chief was also asked about Iran’s plans to withdraw from the Non-Proliferation Treaty (NPT), a key international accord aimed at preventing the spread of nuclear weapons.

The move would be “very regrettable,” he said. “I hope this is not the case. I don't think this would help anybody, starting with Iran. This would lead to isolation, all sorts of problems.”