The United States and Britain launched strikes against 36 targets in Yemen, in the second day of major US operations against Iran-linked groups, following a deadly attack on American troops last weekend.
The Pentagon targeted 13 locations across the country, and reported the strikes hit buried Houthi weapons storage facilities, missile systems, launchers and other capabilities that the Houthis have used to attack Red Sea shipping.
US Defense Secretary Lloyd Austin said the strikes also had support from Australia, Bahrain, Canada, Denmark, the Netherlands and New Zealand.
"This collective action sends a clear message to the Houthis that they will continue to bear further consequences if they do not end their illegal attacks on international shipping and naval vessels," Mr Austin said in a statement.
"We will not hesitate to defend lives and the free flow of commerce in one of the world's most critical waterways."
In a joint statement issued following the strikes, the US and its allies said, "today's strike specifically targeted sites associated with the Houthis' deeply buried weapons storage facilities, missile systems and launchers, air defence systems, and radars."
On Friday, the US carried out strikes in Iraq and Syria against more than 85 targets linked to Iran's Islamic Revolutionary Guard Corps (IRGC) and militias it backs, reportedly killing nearly 40 people.
Those strikes, which were condemned by Iran and by Iraq, were retaliation for a drone strike that killed three US soldiers and wounded more than 40 other American service members in Jordan last Sunday.
Speaking on ABC Insiders, Prime Minister Anthony Albanese said Australia supports the actions of the United States.
"These are proportionate. These are retaliatory for the actions of Iran-backed organisations. And they are not an escalation," he said.
"We think that the United States has got it right. It's important that — given the attacks that have occurred by groups backed by Iran — there be a response. There has been."
But while the US accuses Iran-backed militias of attacking US troops at bases in Iraq, Syria, and Jordan, Yemen's Iran-backed Houthis have been targeting commercial ships and warships in the Red Sea.
The Houthis, who control the most populous parts of Yemen, say their attacks are in solidarity with Palestinians as Israel strikes Gaza. But the US and its allies characterise the Houthi attacks as indiscriminate and a menace to global trade.
The United States has previously carried out more than 10 strikes against Houthi targets in the past several weeks, but they have failed to stop attacks by the group.
The Houthi-run Yemeni News Agency said the US and Britain launched 14 raids on Saturday on the governorates of Taiz and Hodeidah.
Eleven of the attacks targeted the Al-Barah area in the Maqbanah district and areas in the Haifan district, a security source told the news agency. The other three attacks targeted Jabal Al-Jada' in Al-Lahiya district and the Al-Salif district in Al-Hudaydah governorate.
Reuters