Leaders from Australia and Britain are expected to travel to Washington this month to announce how Australia will acquire nuclear subs, which Prime Minister Anthony Albanese described as “the single biggest leap in our defence capability in our history”.

Opposition leader Peter Dutton, who was defence minister when the Aukus partnership between Australia, the US and Britain was formed in 2021, told reporters at the Avalon Air Show he favoured the American Virginia-class submarine.

“It was a proven design, it gave us interoperability with the Americans, and there’ll be more American subs in the Indo-Pacific than there will be British submarines, who will concentrate, quite rightly, particularly given the Russian threat, to continental Europe,” he said.

“I worry that if the government’s taken a decision to go for a cheaper design, that it will delay the delivery of those submarines,” he added, when asked about defence industry speculation that a British submarine would be chosen.

Minister for defence industry Pat Conroy, who last week visited the British submarine shipyard in Barrow-in-Furness, said that Dutton’s comments were “incredibly irresponsible” and that his predecessor was “not privy to the latest information”.

“I’ve got a full briefing on what the UK is doing. I stay in regular contact with the US Navy, and we’ll make announcements very shortly about the optimal path forward on our nuclear propelled submarines,” he said.