The United States has threatened to "obliterate" Iran's power plants in 48 hours over the Strait of Hormuz issue, just a day after President Donald Trump said he was winding down the war, adding complexity to diplomacy anew.

The US administration said on Saturday that if Iran "doesn't fully open, without threat, the Strait of Hormuz, within 48 hours", Washington "will hit and obliterate their various power plants, starting with the biggest one first".

Both the US and Iran threatened to escalate their fighting by targeting energy and fuel facilities, including related US and Israeli assets in the Gulf, which has already started to affect global energy and food costs as the conflict entered its fourth week.

"Following previous warnings, if Iran's fuel and energy infrastructure is attacked by the enemy, all infrastructure of energy, information technology, and desalination facilities belonging to the US and (Israel) in the region will be targeted," said Ebrahim Zolfaqari, a spokesman for Iran's Khatam al-Anbiya Central Headquarters.

Iran's representative to the International Maritime Organization, Ali Mousavi, said ships, except those from "enemies", can pass the Strait of Hormuz with prior coordination with Iranian authorities for security and safety arrangements.

International maritime commitments should also include respect for Iran's territorial integrity and sovereign rights, Mousavi was quoted as saying in Iranian media reports published on Sunday. Tehran stands ready to cooperate with the IMO and other countries to enhance maritime safety and protect seafarers, he added.

US-Israeli attacks against Iran were at the "root of the current situation in the Persian Gulf region and the Strait of Hormuz", he said.

Over the weekend, the US and Israel continued attacks across Iran, striking Tehran, Karaj, Isfahan and Natanz.

The International Atomic Energy Agency reported on Saturday that Iran's Natanz facility for nuclear enrichment has been bombed amid continuing strikes.

Rafael Grossi, head of the IAEA, reiterated his call "for military restraint to avoid any risk of a nuclear accident".

Pirhossein Kolivand, president of the Iranian Red Crescent Society, said the US-Israeli strikes have attacked more than 80,000 civilian places since the beginning of their "aggression", with reports estimating more than 1,500 deaths.

Missiles targeting

Israel In Israel, nearly 200 people were injured by Iranian strikes in the southern cities of Dimona and Arad on Saturday after air defenses failed to intercept at least two ballistic missiles, The Times of Israel reported.

Among those seriously injured were a 12-year-old boy suffering from shrapnel injuries in Dimona and a 5-year-old girl hurt in the subsequent strike in Arad.

Israeli Prime Minister Benjamin Netanyahu has instructed the director-general of his office "to provide the full necessary assistance together with all government ministries", the office said.

Israel has banned large gatherings and closed schools in the south after the attacks.

The IAEA said it was aware of reports of an incident in Dimona involving a missile impact and has not received any indication of damage to a nuclear research center. "Information from regional states indicates that no abnormal radiation levels have been detected," it said.

Meanwhile, in a sign of increasing diplomatic strain, Saudi Arabia has moved to declare Iran's military officials and three other embassy staff members as persona non grata and ordered them to leave the country within 24 hours, according to the Saudi Ministry of Foreign Affairs.

The continued targeting by Iran of Saudi Arabia's sovereignty, civilian objects, civilians, economic interests and diplomatic premises within the kingdom "constitutes a flagrant violation of all relevant international conventions, the principles of good neighborliness and respect for states' sovereignty, the Beijing Agreement, and United Nations Security Council Resolution 2817", the ministry said.

On Sunday, three ballistic missiles were detected around the Saudi capital Riyadh, the Defense Ministry said. "One missile was intercepted, while the other two fell in an uninhabited area," a ministry spokesperson posted on social media.

Agencies and Xinhua contributed to this story.

Contact the writers at jan@chinadailyapac.com