Australia is set to announce a new nuclear-powered submarine fleet using American and British technology, the Australian Broadcasting Corporation said in a report on Wednesday (Sept 15).

"Australia, the United States and Britain are expected to jointly announce a new trilateral security partnership on Thursday, with a focus on aligning technology and regional challenges," ABC said on its website.

The report added: "The ABC understands Australia will use American and British technology to configure its next submarine fleet in a bid to replace its existing Collins class subs with a boat more suitable to the deteriorating strategic environment."

Meanwhile, US President Joe Biden is expected to announce a plan to share advanced technologies in a working group with Britain and Australia, to be known as AUUKUS, Reuters reported, citing a report in Politico news site.

Mr Biden is due to give a 5pm address on Wednesday (5am on Thursday, Singapore time) on national security, but the White House would not provide details.

The working group will enable the three countries to share information in areas including artificial intelligence, cyber, underwater systems and long-range strike capabilities, Politico reported, citing a White House official and a congressional staff member.

As part of the pact, the US and Britain share their knowledge of how to maintain nuclear-defence infrastructure, one of the unidentified sources said.

Both characterised the plan as a move by Western allies to counter China's rise in the military and technology sectors, the report cited by Reuters said.