The US Congressional Budget Office has raised fresh concerns about Aukus, just one day after the US president, Joe Biden, assured the visiting Australian prime minister, Anthony Albanese, that the deal would ultimately be approved by congress.
Biden told Albanese after talks at the White House on Wednesday that the passage of legislation allowing for the transfer of nuclear-powered submarines to Australia was a matter of “not if, but when”.
Biden called on Congress to “pass our Aukus legislation this year” but added: “I believe it will get done.”
On Thursday, however, the CBO published a report warning the sale of between three and five Virginia-class boats to Australia in the 2030s “would reduce the number of attack submarines available to the [US] Navy”.
The report – which said US shipyards were already “struggling” to meet existing demand – may embolden the Republican senator Roger Wicker and other Aukus sceptics who are worried about the impact on the US’s own submarine needs.
The US plans to sell Virginia class nuclear-powered attack submarines (SSNs) to Australia in the 2030s before Adelaide-built submarines start to enter service from the 2040s.
The US Navy has said it “anticipates building additional Virginia class SSNs in the 2030s as replacements for submarines sold to Australia” – but the CBO said this would require the US to build SSNs at the rate of 1.9 to 2.6 a year.
That is because the US navy already plans to purchase between 16 and 21 SSNs in the 2030s.
“Currently, the shipyards are building fewer than 1.5 SSNs a year in addition to beginning construction of Columbia class ships and are facing a backlog of work,” the report said.
“Therefore, it would be very difficult and expensive for the US submarine industry to increase production of attack submarines during a period when it must also build 1 Columbia class ship per year.”
The CBO also raised the question: “Would China be less deterred if the United States reduced the number of its attack submarines to help Australia develop its
submarine force?”
Citing the strong alliance between Washington and Canberra, the report said improving the Royal Australian Navy’s capability “could help offset the U.S. Navy’s potential loss of capability”.
“That loss might even be more than offset because the Australian submarines would be based in the Western Pacific region and therefore could respond more quickly to any conflict with China involving Taiwan or other issues in the South China Sea,” it said.
“However, Australia would control its own submarines, and their participation in any particular conflict would not be guaranteed.”
The report highlighted comments by the Australian defence minister, Richard Marles, in March that the Aukus deal did not include any pre-commitments to the US over a Taiwan-related conflict.
These comments were also cited in an earlier report by the Congressional Research Service, which is separate from the CBO. Both agencies aim to provide legislators with nonpartisan analysis on policy issues.
The Greens’ defence spokesperson, David Shoebridge, said the CBO paper provided “hard truths for Labor and their mates in Defence who are pumping the Aukus submarine deal”.
Shoebridge wrote on X: “There are two possible outcomes: either we spend $50bn on Aukus subs between now and 2033 and then the US refuses to deliver any and it’s all wasted OR we surrender our sovereignty to the US on the decision to go to ANY war they want. That’s a hell of a deal.”
The Australian government has repeatedly argued it will retain sovereign control of the submarines, despite arguments from former prime ministers Malcolm Turnbull and Paul Keating that the multi-decade Aukus arrangement relies on US support and reduces Australia’s room to move.
The CBO estimates the US navy’s plans would require annual shipbuilding funding to be between 31% and 40% higher than the average over the past five years.
The White House last week released a supplemental budget request to Congress for a further $3.4bn to boost the US submarine industrial base in an attempt to win over Aukus doubters.
Wicker, who represents Mississippi in the US Senate, responded to that by calling it a “welcome start” but said the US must “meet the obligations of the Aukus agreement without putting our own submarine fleet in jeopardy”.
Albanese said on Thursday – the final of his four-day official visit to the US – that Australia was seeking to prevent conflict by “making it crystal clear to any aggressor that the risk of conflict far outweighs any potential benefit”.
Speaking at a luncheon at the US State Department, Albanese said Australia was stabilising its relationship with Beijing but remained “clear-eyed” about the challenges. He is due to visit China late next week.
