US Congress planning to approve an extra $US1bn on submarine production in boost for AUKUS

The US Congress is planning to rectify a cut to submarine production amid warnings that the move could have harmed the AUKUS pact and let down Australia.

The US Congress is moving to rectify the Navy’s proposal to build just one Virginia-class nuclear submarine next year, with a key AUKUS supporter warning the production cut would otherwise imperil the pact.

In March, the Navy used its annual budget request to seek funding for one new vessel – rather than the two it is supposed to produce every year – which sparked widespread concern about Australia’s deal to buy three Virginia-class boats from the US in the 2030s.

The US Congress is planning to approve an extra $US1bn to ensure the production of a second submarine next year as part of the AUKUS deal.

But the House Armed Services Committee is now planning to approve an extra $US1bn ($A1.5bn) to ensure production of a second submarine next year, as part of a broader effort to stem major delays that have plagued the US defence industrial base.

Democratic Party congressman Joe Courtney, the co-chair of the congressional AUKUS caucus, said that “for the people of Australia … it is imperative that we match their commitment by keeping our submarine construction plan on track”.

Under laws signed by US President Joe Biden in December, the submarine transfers to Australia in the 2030s can only occur if the president at the time affirms they will not degrade the US Navy’s fleet.

“Taking a submarine out of our inventory, which is already below the Navy’s requirement of 66 attack submarines, will make that decision more difficult,” Mr Courtney told a committee hearing on Wednesday (local time).

“That’s not just an opinion – it’s simple math.”

He told his congressional colleagues that “for the sake of AUKUS”, they needed to approve the extra spending and keep the pressure on the Navy to fast-track its submarine build rate.

“The sudden about-face in the Navy’s budget undermines the steady progress that Congress made to eliminate procurement instability and grow the submarine industrial base,” Mr Courtney said.

America’s submarine shipbuilders are currently delivering about 1.3 Virginia-class vessels per year, with the Navy predicting the two-per-year pace will not be reached until 2028 and that its fleet will shrink to 47 boats by the end of the decade.

Earlier this month, 120 House lawmakers backed plans to restore the funding to build a second Virginia-class submarine next year, saying in a joint letter that the vessel was “one of our most distinct national security advantages”.

Navy chiefs had argued delaying the construction of one vessel was necessary to allow the submarine industrial base to properly integrate major long-term investments to accelerate production.