The International Atomic Energy Agency warned of "the paramount importance of adhering to the seven pillars for ensuring nuclear safety and security during a conflict."

The director general of the International Atomic Energy Agency on Saturday demanded "maximum military restraint" from the US and Israel as it confirmed reports that strikes had targeted a location close to Iran's Bushehr Nuclear Power Plant, killing at least one person.

In a statement released via social media, the IAEA relayed a message from Director General Rafael Mariano Grossi, who expressed "deep concern about the reported incident."

Grossi warned that nuclear power plants or nearby areas "must never be attacked, noting that auxiliary site buildings may contain vital safety equipment" and stressed "the paramount importance of adhering to the seven pillars for ensuring nuclear safety and security during a conflict."

The IAEA said the attack near the Bushehr plant, Iran's only operational nuclear power facility, was the fourth such attack since Israel and the US began its invasion of Iran on February 28. The plant lies in a city inhabited by about 250,000 people.

A security staff member was killed by a projectile fragment and a building on the Bushehr site was impacted by shockwaves and fragments. Grossi said that no increase in radiation levels was reported.

Iranian Foreign Minister Abbas Araghchi also condemned the Bushehr strike and issued a reminder of the "Western outrage about hostilities near Zaporizhzhia Nuclear Power Plant in Ukraine" when Russia attacked the site.

"Israel-US have bombed our Bushehr plant four times now. Radioactive fallout will end life in [Gulf Cooperation Council] capitals, not Tehran. Attacks on our petrochemicals also convey real objectives," said Araghchi.

Al Jazeera reported that at least two petrochemical facilities had been hit by the US and Israel in southern Iran’s Khuzestan province, an energy hub in the country. At least five people were injured in those attacks,

Iranian news agency Mehr reported that the state-run Bandar Imam petrochemical complex, which produces liquefied petroleum gas and chemicals as well as other products, sustained damage.

President Donald Trump said late last month that he would delay any attacks on Iran's energy infrastructure until April 6 and said the delay was "subject to the success of the ongoing meetings and discussions.”

He has threatened to destroy Iran's power plants and other civilian infrastructure if Iranian leaders don't end the blockade on the oil export waterway the Strait of Hormuz, which they began in retaliation for the US-Israeli strikes that started more than a month ago and which has fueled skyrocketing global energy prices.

The threat amounted to Trump warning that he could soon commit a war crime, said international law experts.