U.S. President Donald Trump warned Iranian forces on Monday that they would be “blown off the face of the Earth” if they attempted to target U.S. ships in the Strait of Hormuz or Persian Gulf.

Iran had "no pre-planned programme" to attack oil facilities in the United Arab Emirates, Iranian state TV said Monday, after the UAE blamed the Islamic republic for a drone strike at an energy installation in Fujairah.

Authorities in the emirate said the strike injured three Indian nationals who were taken to hospital. The UAE meanwhile said it had been targeted by a fresh Iranian barrage which it described as a "dangerous escalation", amid a ceasefire in the Middle East war.

Two people were injured when a residential building was targeted in Oman's Bukha along the coastline of the Strait of Hormuz, state media reported on Monday.

An Israeli military official said Monday that the army remained on high alert and was monitoring the situation after a U.S. admiral said forces destroyed six Iranian boats and shot down missiles.

U.S. President Donald Trump said Iran had "taken some shots" but caused little harm in the Strait of Hormuz Monday, while urging South Korea to join the war after one of its vessels was hit.

The United States has destroyed six Iranian boats and shot down missiles and drones fired at U.S. Navy and commercial vessels by Tehran's forces, a top U.S. admiral said Monday.

The UAE said Monday that its air defenses were dealing with Iranian missile and drone attacks, after saying that it previously intercepted three missiles over its territorial waters earlier in the day.

A drone strike meanwhile caused a fire at an energy installation in the emirate of Fujairah, authorities said.

The U.S. military said Monday that two American-flagged merchant ships had successfully transited the Strait of Hormuz after it launched a new initiative to restore traffic. Iran has effectively controlled the critical waterway since the U.S. and Israel launched the war in late February.

Breaking Iran's chokehold over the strait would ease global economic concerns and deny Tehran a major source of leverage in talks aimed at ending the war. But U.S. President Donald Trump's latest effort also risks reigniting full-scale fighting as the U.S. and Iran steadily ramp up pressure.

Israeli police on Monday warned people not to defy the cancelation of a major pilgrimage near the border with Lebanon, scrapped because of hostilities with Hezbollah, while local media reported thousands had gathered at the site.

Fighting between Israeli forces and Hezbollah is ongoing in southern Lebanon despite a ceasefire in effect since mid-April.

Iranian media said Monday that a U.S. navy frigate was targeted by two missiles in the Strait of Hormuz, after President Donald Trump said US forces would begin guiding ships through the waterway.

"The frigate, which was sailing on Monday in the Strait of Hormuz, in violation of navigation and maritime safety rules near (the port of) Jask, was targeted by a missile attack after ignoring a warning from the Iranian navy," the Fars news agency said, without citing a source.