Biden vows 'ironclad' support for Israel against Iran

US President Joe Biden promised "ironclad" support for Israel against Iranian attacks Saturday, after holding an urgent meeting with his top security officials over the spiralling crisis in the Middle East.

"I just met with my national security team for an update on Iran's attacks against Israel. Our commitment to Israel's security against threats from Iran and its proxies is ironclad," Biden said on X, posting a picture of the meeting in the White House Situation Room.

Iran on Saturday launched dozens of drones at Israel that will take hours to reach their targets, Israel's military said, an attack that may trigger an escalation between the regional archenemies.

Tehran had vowed to retaliate for Israel's attack on Iran's embassy compound last week in Damascus that killed a senior commander in the Iranian Revolutionary Guard Corps' overseas Quds Force and six other officers.

The White House said Biden was being briefed regularly on developments in the region, where the American military shot down Iranian drone aircraft headed toward Israel, according to three US officials.

The meeting in the Situation Room, a crisis management centre deep within the West Wing of the White House, was attended by Secretary of State Antony Blinken, Defense Secretary Lloyd Austin, Central Intelligence Agency Director William Burns, Director of National Intelligence Avril Hines, national security adviser Jake Sullivan and other officials, the White House said. 

Earlier on Saturday, Austin spoke with Israeli Defense Minister Yoav Gallant to discuss "urgent regional threats," the Pentagon said, and reiterated full American support for Israel against attacks by Iran and its proxies. 

Jake Sullivan, Biden's national security adviser, relayed a similar message of US support to his own Israeli counterpart, Tzachi Hanegbi, he said in a post on X.

Israel subsequently put its military on full alert and cancelled all educational and other youth activities.

On Friday, Biden warned Iran against retaliation even while predicting the attack may be imminent. "We are devoted to the defence of Israel. We will support Israel. We will help defend Israel and Iran will not succeed," he said.

Leading lawmakers from both the Democratic and Republican parties expressed support for Israel against an Iranian attack. 

The US House of Representatives will make a change in its schedule to consider legislation that supports Israel and holds Iran accountable, Republican House Majority Leader Steve Scalise said in a statement.