In September 2021, the Prime Minister Scott Morrison announced that Australia would scrap its existing contract for Attack-class submarines with France and instead build nuclear-powered submarines with the support of the United States and United Kingdom, a "forever partnership" called AUKUS.

The Australian Government has spent $2.4 billion so far on the Attack-class submarine contract, which it signed in 2016.

The next step for nuclear-powered submarines is an 18-month taskforce to assess infrastructure needs, waste disposal, and other considerations.

One concern for the nuclear-powered submarine timeline is how long Australia's current submarines, the Collins-class, can remain in use. They were originally expected to be decommissioned in 2026; under the old agreement the plan was to extend their lives until the early 2030s.

The federal Opposition says the new submarines may not be constructed until 2040.

In the meantime, the US is apparently unlikely to lease nuclear-powered submarines and buying them "off the shelf" would take at least five years.