Yemen’s Iran-aligned Houthi militants have ‌fired on Saudi oil installations in two ports on the Red Sea coast but the United States has held back from launching air strikes on Iran itself for the first night in two weeks.

There was ‌no immediate explanation from from the US of why it had abruptly halted a streak of 13 nights of escalating strikes since an interim deal to end hostilities collapsed, in retaliation for Iranian attacks on shipping in the Strait of Hormuz.

“It ‌seems that our dear Iran had a peaceful night last night,” Health Ministry spokesman Hossein Kermanpour said on X.

After the quiet night in Iran, there were also no reports on Saturday of attacks from Iran on its Gulf neighbours, which have also been taking place daily in response to the US attacks.

However, the strikes from Iran’s Houthi allies on Saudi Arabia were a sign that the war that has disrupted energy supplies from the Gulf could be spreading to a second major shipping route, and reigniting Yemen’s own civil war.

Houthi military spokesman Yahya Saree said the group had successfully struck sites belonging to Saudi ‌state oil giant Aramco in ‌Jizan and Yanbu.

Houthi forces have struck sites belonging to Saudi oil firm Aramco, spokesman Yahya Saree says. Photo: AP

Video shared ⁠on social media and verified by Reuters showed a large column of smoke rising from the direction of the Aramco refinery in Jizan.

Two Asia-based ​trading sources said that they had been informed of potential damage to fuel and oil storage sites at Jizan.

In Yanbu, two ballistic missiles aimed at oil installations were intercepted by a US-made Patriot battery operated in Saudi Arabia by the Greek military under an agreement with the country, Greek security sources said.

Yanbu is Saudi Arabia’s main Red Sea oil port, where millions of barrels a day are loaded, and has become the main route out for Saudi oil skirting the Strait of Hormuz, which has been blockaded by Iran.

Jizan, on the Red Sea close to the Yemeni border, is the site of a ⁠refinery with a capacity of 400,000 barrels per day.

Houthi-made mock missiles and drones on display in Sana’a, Yemen. Photo: EPA

In Yemen, the air force of the Saudi-backed internationally recognised government, which ‌has opposed the Houthis for ​more than a decade, struck Houthi missile and drone launch sites and arms depots in the Marib and al-Jawf provinces, Yemeni officials said.

Earlier, the Saudi-led military alliance said it had bombed Houthi military positions on Friday ​in the Red ‌Sea port of Hodeidah.

The Yemeni officials said both sides in Yemen’s civil war were mobilising forces along the front.

Saudi Arabia has led an Arab coalition battling against the Houthi militia for more ​than a decade since the Iran-aligned fighters captured Yemen’s capital Sanaa.

The Yemeni civil war, during which hundreds of thousands of people died from fighting and famine, has been paused under a ceasefire since 2022.

But that truce broke down this month, with the Houthis effectively joining the wider war their Iranian allies have waged since being attacked by the US and Israel.

The Houthi movement has declared ​a ​naval blockade of Saudi Arabia over the past week, and Houthi leader Abdul Malik ​al-Houthi said all Saudi oil facilities could be targets.

The move has contributed in recent days to one ‌of the war’s sharpest rises in global oil prices, with Brent crude spiking above $US100 a barrel for the first time since May.

US President Donald Trump on Friday vowed “major military punishment” for Iran and the Houthi movement after the Houthis struck two Saudi tankers in the Red Sea.

An interim truce meant to end the war effectively collapsed two weeks ago, with US forces striking targets in southern Iran in response to Iranian disruption of shipping in the Strait of Hormuz.