President Donald Trump has extended his deadline for Iran to reopen the Strait of Hormuz, saying the U.S. will hold off on power plant strikes for five days.

Trump made the announcement on his Truth Social site Monday, hours ahead of a deadline later in the day.

Prime Minister Nawaf Salam has said that members of Iran's Revolutionary Guards are commanding Hezbollah's operations in the group's ongoing war against Israel.

In an interview Sunday with the Al Hadath network, Salam once again lashed out at Hezbollah for dragging Lebanon into the Middle East war by firing rockets on Israel.

The Israeli military has announced it was expanding its ground campaign against Hezbollah in Lebanon, warning of a lengthy operation, after Beirut condemned what it called Israel's flagrant violations of Lebanese sovereignty.

Israeli forces were ordered Sunday to destroy bridges they said were used by the Hezbollah to cross the Litani River, and Lebanese official media reported Israeli raids in the south.

The Israeli military on Monday said its own artillery fire killed an Israeli civilian a day earlier near the northern border with Lebanon, where its forces are fighting Hezbollah.

After opening an investigation, the military said "the initial findings suggest that the Israeli civilian was killed by IDF artillery fire conducted to support IDF soldiers operating in southern Lebanon".

Israel said it struck "Hezbollah" targets in south Lebanon on Sunday shortly after the military was ordered to destroy bridges allegedly used by the Iran-backed group across the Litani River.

Iran's military threatened on Sunday to completely shut down the strategic Strait of Hormuz if U.S. President Donald Trump acts on threats to target the country's power plants.

U.S. President Donald Trump on Saturday gave Iran 48 hours to reopen the Strait of Hormuz to shipping or face the destruction of its energy infrastructure, as Tehran launched its most destructive attack yet on Israel.

Iran's powerful parliament speaker Mohammad Bagher Ghalibaf threatened on Sunday to irreversibly destroy vital infrastructure across the region if the United States and Israel attacked its own.

Israeli Prime Minister Benjamin Netanyahu vowed on Sunday to pursue senior commanders of Iran's Revolutionary Guards "personally", during a visit to an Israeli town struck by an Iranian missile the previous day.

Iranian missile strikes on two southern Israeli towns wounded more than 100 people on Saturday, medics said, after Israeli air defence systems failed to intercept the projectiles.