Australian prime minister Anthony Albanese has confirmed that three Australian Defence Force personnel were aboard a United States submarine that sank an Iranian naval vessel during escalating conflict in the Middle East, though he insisted no Australian personnel took part in the attack.
Speaking on Friday, Albanese said the Australians were embedded on the submarine as part of training arrangements linked to the AUKUS defence partnership, which aims to deepen military cooperation between Australia, the United States and the United Kingdom.
“We wouldn’t normally confirm such an issue, but given our National Security Committee meetings, in the public interest I can confirm that there were three Australian personnel onboard that vessel,” Albanese said.
“I can confirm also, though, that no Australian personnel have participated in any offensive action against Iran.”
The prime minister’s confirmation followed earlier reports that Australian sailors or officers were present aboard the US submarine that torpedoed and sank the Iranian frigate IRIS Dena in the Indian Ocean.
The attack killed at least 87 Iranian sailors. Thirty-two survivors were rescued by the Sri Lankan navy, while up to 180 crew members were believed to have been aboard the vessel at the time.
The Iranian warship was reportedly returning from a naval exercise organised by India in the Bay of Bengal when it was attacked in international waters.
The United States has not formally identified the submarine responsible for the strike. However defence trade publications have reported that the USS Minnesota, a Virginia-class attack submarine, carried out the operation.
The Minnesota had previously rotated through HMAS Stirling naval base in Western Australia in 2025 as part of the expanding naval cooperation between the United States and Australia.
US defence secretary Pete Hegseth confirmed the strike in a Pentagon briefing, describing the sinking as a decisive demonstration of American military power.
“An American submarine sank an Iranian warship that thought it was safe in international waters. It was sunk by a torpedo, a quiet death,” Hegseth said.
Iran condemned the attack. Foreign minister Seyed Abbas Araghchi described it as an “atrocity at sea” and warned the United States would regret the precedent created by the strike.
The incident has also intensified political debate in Australia about the country’s deepening military integration with the United States under the AUKUS agreement.
Greens senator David Shoebridge said the presence of Australian personnel on the submarine made Australia effectively part of the conflict.
“This makes Australia obviously, clearly, unambiguously part of an illegal war,” Shoebridge said.
He argued that Australian personnel embedded in US military assets would inevitably become involved in American combat operations.
Under the AUKUS training arrangements, more than 50 Australian sailors and officers are currently embedded in the US attack submarine fleet as part of preparations for Australia to operate its own nuclear-powered submarines in the coming decades.
According to the Royal Australian Navy, roughly one in ten crew members serving aboard US Navy attack submarines is Australian during training rotations.
Some critics within the Labor movement have also raised concerns. Former Labor senator Doug Cameron said the development confirmed fears that Australia could be drawn into future conflicts involving the United States.
“These are grave, distressing and terrible developments, especially for a Labor government,” Cameron said.
Legal experts have also examined the circumstances surrounding the strike. Donald Rothwell, a professor of international law at the Australian National University, said that once armed conflict had begun between the United States and Iran, the Iranian naval vessel could be considered a lawful military target.
“Armed conflict has commenced and the members of the Iranian navy are legitimate combatants for those purposes,” Rothwell said.
However, questions remain about whether adequate assistance was provided to survivors after the sinking.
Juliette McIntyre, a senior lecturer in law at the University of Adelaide, said international humanitarian law normally requires assistance to shipwrecked combatants, though operational constraints for submarines could complicate that obligation.
The strike marks the first time since the second world war that a US submarine torpedo has sunk an enemy vessel, highlighting the escalating military confrontation between Iran and US-aligned forces.
