Taiwan has made the indigenous sub programme a key part of an ambitious project to modernise its armed forces as Beijing stages almost daily military exercises to assert its sovereignty.

Australia has agreed to invest US$3 billion in the US submarine industrial base as part of Aukus.

A report showed most of the cost of the submarine programme incurred in the two decades from 2033.

The US, Australia and Britain unveiled details of a plan to provide Australia with nuclear-powered attack submarines from the early 2030s to counter China's ambitions in the Indo-Pacific.

Britain and Australia will embark on building a new model, also nuclear-powered and carrying conventional weapons, dubbed the SSN-Aukus.

Government modelling showed 20,000 jobs, including 8,500 in submarine construction, would be created in Australia over 30 years, reports show.

Adelaide was chosen as the base in 2016 when France won a US$33 billion deal to build 12 submarines for Australia before Canberra ditched that in favour of Aukus, causing fury in Paris.

After 18 months of negotiations, it is anticipated that Australia will reveal plans to obtain eight nuclear-powered submarines.

The Paris Court of Appeal will deliver its decision on April 11.

The delivery of the new nuclear submarines could take years, potentially leaving Australia short of capacity at a time when China is increasing its assertiveness in the region.

But this week's clash has done little to change the way the IAEA approaches the submarine plan, which is still being developed.

Najib was defence minister when the deal was signed to buy two Scorpene-class submarines and one Agosta submarine from French naval dockyards unit DCN, now part of Thales, in a deal worth US$1.2 billion.