TEHRAN - Iran on Monday faces a deadline by President Donald Trump to open up the crucial Strait of Hormuz or face a major US assault on power plants, as Israel warned of weeks more of war.
Israel also gave the clearest signs yet it intends a ground campaign into Lebanon, destroying a key bridge as it vows to crush Hezbollah, the Shia Muslim movement backed by Iran.
Trump, after enthusiastically backing Israel in the war the two countries launched on February 28, is under political pressure as fuel prices rise, the result of Iran's attempts to retaliate in the oil-rich Gulf.
Trump on Saturday threatened to "obliterate" Iran's power plants if it did not within 48 hours end its partial blockade of the Strait of Hormuz, the narrow waterway into the Gulf through which one-fifth of the world's oil flows.
The deadline, based on the time of his social media posting, would be 23:44 GMT, early morning Tuesday in Iran and Monday evening in Washington.
Iran's military command responded defiantly, saying that if Trump goes ahead, it would strike Israel's "power plants, energy and information and communications technology infrastructure" -- along with power plants in regional countries hosting US bases and companies with American shareholders.
"If the United States' threats regarding Iran's power plants are carried out... the Strait of Hormuz will be completely closed, and it will not be reopened until our destroyed power plants are rebuilt," a process that could take years, the operational command warned.
Iran's powerful parliament speaker Mohammad Bagher Ghalibaf warned that vital infrastructure across the region would "be considered legitimate targets and will be irreversibly destroyed".
And the energy minister said US-Israeli strikes have already inflicted "heavy damage" on Iran's water and energy infrastructure.
Trump's threats drew rare concern from exiled Iranians supportive of the war, launched weeks after the Islamic republic crushed widespread demonstrations, killing thousands of people.
Reza Pahlavi, son of the late shah ousted in the 1979 Islamic revolution, called on Washington and Israel to target the "apparatus of repression" but to protect "Iran's civilian and vital infrastructure, which our people need to rebuild the country".
Trump has offered varying timelines and objectives for the war, saying Friday he was considering "winding down" the operation, a day before his threat to power plants, which would mark a significant escalation.