The US, Australia and the UK are to unveil a multi-stage programme to supply Canberra with nuclear-powered submarines that will culminate in the development of a next-generation boat based on a British design.
The key elements of the so-called Aukus security pact, which will stretch for decades, will include the provision of US submarines to Australia while its own fleet is developed, according to four people familiar with the agreements.
President Joe Biden will meet his Australian and British counterparts in San Diego on Monday to announce the deal, which fleshes out the terms of a pact signed in 2021 and sets a pathway for tens of billions of dollars of investment.
Australia wants nuclear-powered submarines to replace its current Collins-class fleet, which would give it stealthier boats that are quieter and can travel longer distances without surfacing and revealing their position. The move is part of a strategic shift to help Australia and the US, and other allies, counter China in the Indo-Pacific.
Under the agreed plan, the US will initially send several Virginia class submarines to Australia to train Australian officers on how to operate sensitive nuclear-powered submarines. The US will later sell several Virginia class boats to Australia to fill the capability gap that will emerge when its current fleet of Collins-class submarines is retired.
For a more long-term solution, Britain and Australia will jointly develop a “hybrid” vessel. This will be based on the UK’s next-generation submarine design, currently dubbed SSN (R), which is due to replace the Astute class. Some people involved in the process have nicknamed the modified version the “SSN Aukus”.
British industry, led by BAE Systems and Rolls-Royce, has worked on the design but industry insiders said it could still accommodate substantial Australian input. Under the original timetable, the new fleet of attack boats was not expected to enter service until the 2040s at the earliest.
Industry analysts say such a project would only make economic sense if the UK and Australia shared a common platform, although the weapons and combat systems could differ. The US is expected to supply a lot of the weapons systems on the submarine, partly because of the need to ensure interoperability with US boats.
The deal will require significant UK government investment given existing shipbuilding constraints. It will also help to underpin Britain’s submarine enterprise, which has historically been dogged by delays and cost overruns.
Several people familiar with the Aukus discussions said the UK would have a bigger role than was imagined when the three countries started discussing how to proceed with Aukus was launched in September 2021.
“The UK was going to be an also-ran in this deal, picking up the pieces,” said one naval expert. “Now, this will help to cement its position as a country with nuclear-powered submarines.”
One person familiar with the agreement said Australia may provide money to boost capacity at US submarine shipbuilding yards, addressing concerns in Congress that Aukus will add to the US navy’s production backlog.
In January, the top Democrat and Republican on the Senate armed services committee wrote to Biden to stress that Aukus should not bring the US submarine industrial base to a “breaking point” and create a “zero-sum game” for scarce resources as the US boosts its capability to counter China.
The three allies are also working on a second pillar of Aukus, which includes, hypersonic weapons, electronic warfare and undersea capabilities.
While there is optimism that the US has found ways to overcome legacy restrictions on sharing technology and sensitive information with allies to make sure that the submarine programme is a success, Washington has made much less progress removing obstacles to the second pillar.
London, Canberra and some US officials are concerned that a lack of progress on the second pillar will undermine Aukus by delaying work on areas that were supposed to deliver earlier results while the nations work on the decades-long submarine plan.
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