Australia’s apparent absence from the mission comes days after the US Congress passed long-awaited legislation to help facilitate the $368 billion AUKUS submarine pact.

The passage of the AUKUS-enabling bill allows the sale of three Virginia-class ­nuclear submarines to Australia,enables Australian workers to be trained in US shipyards,and exempts Australia from a maze of US export controls on the transfer of sensitive military technology.

However,on Monday,Prime Minister Anthony Albanese downplayed the notion that Australia had rejected a formal request from the US to join its multinational taskforce,telling ABC radio:“This wasn’t a request,to be clear,from the US government to my government. This was a general request to a range of nations for support there.”

“Our first priority is in our own region,and certainly the United States understands the important role that we’re playing,including freedom of navigation and other issues in our region.”

The new taskforce falls under the Combined Maritime Forces – a multinational alliance responsible for defending the world’s shipping lanes.

It is not yet clear what each participating country has agreed to do as part of the expanded mission,including whether they would follow America’s lead by shooting down Houthi missiles and drones if necessary.

Australian Defence Force chief Angus Campbell was expected to discuss the operation at a virtual meeting with Austin on Tuesday evening.

Support from allied countries was sought by the US as tensions escalated in the Middle East amid the Israel-Hamas war and attacks on commercial ships in the Red Sea by Houthi rebels intensified.

Those attacks have prompted major shipping countries to suspend voyages through a crucial waterway that carries 10 per cent of the world’s cargo,and have fuelled concern of a broader conflict in the region.

Earlier this month,a US destroyer and three commercial ships came under drone and ballistic missile attacks,marking a significant escalation.

The Houthi rebels have threatened to target all ships heading to Israel and warned international shipping companies against using Israeli ports.

Australia’s hesitation to commit to the operation had been questioned by the opposition over the weekend. Liberal MPs also demanded an explanation if the government was not going to offer a warship as part of the mission.

Comment has been sought from Defence Minister Richard Marles on whether Australia will instead offer some other type of contribution,such as more troops in the Middle East. He is yet to respond.

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