The United States has indications that Iran is preparing to imminently launch a ballistic missile attack against Israel that could be at least as large as a strike that Tehran staged earlier this year, US officials said.
The United States is actively supporting preparations to defend Israel against a new Iranian missile attack, a senior White House official said.
"A direct military attack from Iran against Israel will carry severe consequences for Iran," the official said.
A second US official said that the Iranian strike could be as large or potentially bigger than one on April 14 in which Tehran launched more than 300 missiles and drones.
Iran's mission to the United Nations did not immediately respond to a request for comment.
The April attack - the first-ever direct Iranian strike on Israel - was in retaliation for what Iran called an Israeli strike on its Damascus consulate that killed seven Islamic Revolutionary Guard Corps officers, including two senior commanders.
It caused only modest damage inside Israel due to air defence interceptions not only by Israel, but by the United States, Britain and other allies in the region.
The US warning of a looming Iranian strike followed Israel's announcement that its forces staged raids into southern Lebanon in a limited incursion as it pursues two weeks of strikes against Hezbollah militants that have killed the Iran-backed group's leader and senior commanders.
Israeli leaders have vowed to pursue operations against the militants until it is safe for civilians to return to their homes in northern Israel from which they were evacuated after Hezbollah began missile strikes on October 8, a day after Hamas' assault into Israel.
The Hamas assault triggered the ongoing Israeli offensive that has devastated Gaza.
The Pentagon has said that the United States would come to Israel's defence if Iran launched another attack.
It has moved thousands of additional US forces into the region to bolster its ability to defend Israel and US forces in the region. Pentagon officials say it is even better prepared for a new Iranian attack than it was in April.
Israel's defence, however, could also depend on whether Middle East nations will rally again to aid Israel.
Saudi Arabia and other Gulf allies have air defences that could assist in Israel's defence, and nations like Jordan could decide whether to allow countries aiding Israel to use its airspace.
An Iranian attack, should it occur, could pose a major challenge to President Joe Biden's administration goal for his Middle East policy: preventing the Israel-Hamas war from ballooning into a regional conflict.
