Dubai: Iranian President Masoud Pezeshkian announced that 14 million Iranians, including himself, have volunteered to sacrifice their lives in the ongoing war, as tensions across the Middle East escalate.

Taking to X, he wrote, "Over 14 million proud Iranians have, up to this moment, declared their readiness to sacrifice their lives in defence of Iran. I too have been, am, and will be a sacrificer for Iran."

The announcement comes as Iran rejected a 45-day ceasefire proposal, insisting on a permanent end to the conflict, while U.S. President Donald Trump’s ultimatum to strike Iranian infrastructure approaches.

Trump warned Monday that he is “not at all” concerned about committing possible war crimes as he threatened to destroy Iranian infrastructure if Tehran does not meet his Tuesday 8 p.m. EST deadline to reopen the Strait of Hormuz.

U.N. Secretary-General Antonio Guterres cautioned the U.S. that attacking civilian infrastructure is banned under international law, his spokesperson said Monday.

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The conflict intensified overnight with a new wave of attacks. Israel carried out strikes on Iran, and Iran retaliated with missile fire targeting Israel and Gulf Arab neighbours.

Since the war began, more than 1,900 people have been killed in Iran, though the government has not updated the toll for several days. In Lebanon, over 1,400 have died and more than 1 million have been displaced. Eleven Israeli soldiers have also been killed, while in Gulf Arab states and the occupied West Bank, over two dozen fatalities have been reported. In Israel, 23 people have died, and 13 U.S. service members have been killed.

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In Saudi Arabia, overnight attacks struck a petrochemical complex in Jubail, a witness told AFP, hours after similar Iranian installations were targeted.

"An attack caused a fire at the SABIC plants in Jubail. The sounds of explosions were very loud," the source said, referring to the Saudi Basic Industries Corporation.

Jubail is home to one of the world’s largest industrial cities, producing steel, gasoline, petrochemicals, lubricants, and chemical fertilisers. Workers in affected areas were evacuated from living quarters, the witness said. AFP reached out to SABIC for comment.

Earlier, Israel’s Defence Minister Israel Katz said his country conducted a "powerful strike" on Iran's largest petrochemical facility in Asaluyeh, while Iranian media reported multiple explosions at the site.

The attack on Jubail coincided with Saudi air defence forces intercepting seven ballistic missiles targeting the kingdom’s eastern region, according to a defence ministry spokesperson.

"Parts of ballistic missile debris fell around power facilities; damage assessment is underway," the ministry said in a post on X.

Authorities also temporarily closed the King Fahd Bridge, connecting Saudi Arabia and Bahrain, as a precaution following security alerts.

"The movement of vehicles across King Fahd Bridge has been suspended as a precautionary measure," said the General Authority for King Fahd Causeway.

The bridge, a 25-kilometre (16-mile) series of bridges linking Saudi Arabia and Bahrain, was later reopened to traffic.

Saudi Arabia has accused Iran of repeatedly targeting its energy installations and infrastructure since Tehran launched a sustained offensive across the Gulf following attacks by Israel and the U.S. on Iran in late February.