US president Joe Biden has promised Israel his country’s “ironclad” support, as Iran vows retaliation for the deadly strike on the Iranian consulate in Syria earlier this month.
The US military believes Israel carried out the airstrike on Iran’s diplomatic station, which killed two top generals and others.
Israel has not commented on the attack, but Tehran says it holds Israel responsible.
The White House says it had no prior knowledge of the operation, but has repeatedly promised to back Israel in the face of Iranian threats.
Mr Biden spoke on Wednesday alongside Japanese Prime Minister Fumio Kishida, who is in Washington for an official visit.
“We also want to address the Iranian threat to launch a significant attack on Israel,” Mr Biden said during a joint news conference.
“Our commitment to Israel’s security against these threats from Iran and its proxies is ironclad.”
“We say it again, ironclad, and we’re going to do all we can to protect Israel’s security,” Mr Biden said.
Earlier on Wednesday, Iran’s supreme leader repeated a promise to retaliate against Israel.
And Israel’s foreign minister threatened on Wednesday that his country’s forces would strike Iran directly if the Islamic Republic launched an attack from its territory against Israel.
Since Israel’s war in Gaza against Hamas began six months ago, there have been near-daily exchanges of fire along the Israel-Lebanon border between Israeli forces and the Lebanese militant group Hezbollah, which is backed by Iran.
Tehran also backs an umbrella group of Iraqi militias that have attacked US military bases and positions in Syria and Iraq.