Israel has launched a new wave of strikes and says its attacks on Iran "will escalate and expand."
The threat on Friday comes after U.S. President Donald Trump claimed talks on ending the war were going well and gave Tehran more time to open the Strait of Hormuz, though there have been no signs of Iran backing down.
With stock markets reeling and economic fallout from the war extending far beyond the Middle East, Trump is under growing pressure to end Iran's chokehold on the strait.
Iran, meantime, fired new rounds of missiles at Israel and its Gulf Arab neighbors, damaging two port facilities in Kuwait.