WHICH SUBMARINE WILL FLOAT ANTHONY ALBANESE'S BOAT?

The Royal Australian Navy is seeking to acquire at least eight nuclear-powered submarines to replace the retiring conventionally powered Collins-class boats. It will be the largest defence acquisition in Australia's history, costing at least $100 billion.

* Experts have speculated about five boat options: the US Virginia-class; the British Astute-class; a hybrid based on the UK boat with a US weapons system; a newly developed US boat, the SSN (X); or a new British boat, the SSNR.

* The fifth British Astute-class boat, HMS Anson, embarked on its inaugural voyage last month, with two more under construction.

* Work is under way in the UK to design the Astute-class's replacement, the SSNR, which will notably have a vertical launch system allowing it to carry new missile types.

* The US Navy has been rolling out Virginia-class boats since 1998 but is aiming to procure the SSN (X) in the mid-2030s as its successor.

* It's been reported Prime Minister Anthony Albanese, US President Joe Biden and British leader Rishi Sunak will unveil the AUKUS submarine deal in San Diego next week.