Australia will boost its defence forces by some 30 per cent by 2040, Prime Minister Scott Morrison said on March 10, describing it as the country’s largest military build-up in peacetime.

The force would grow by 18,500 personnel to 80,000 over the 18-year period, at a cost of some A$38 billion (US$27 billion), the premier said at an army barracks in Brisbane.

Morrison, who is expected to call a general election in May, told a news conference that the military build-up was a recognition by his government of the “threats and the environment that we face as a country, as a liberal democracy in the Indo-Pacific”.

The Australian leader said some of the new troops would support a future nuclear-powered submarine fleet, promised under a new Australia-Britain-US defence alliance, AUKUS.

Australia says it plans to arm the submarines with conventional weapons but has yet to decide on the details of the programme, including whether to opt for a fleet based on US or British nuclear-powered attack submarines.

The AUKUS alliance would make Australia the only non-nuclear weapons power with nuclear-powered submarines, capable of travelling long distances without surfacing.

Defence minister Peter Dutton said the build-up of forces, to be focused on uniformed troops, would provide a credible deterrent from expansionist military threats.

Beyond submarines, the new forces would be deployed in areas including space, cyber operations, naval assets, and land and sea-based autonomous vehicles, he said.