Satellite imagery from China has unearthed what could be a new or upgraded class of nuclear-powered attack submarine, with one expert warning Australia has a lot of catching up to do.
The discovery by satellite imagery provider Planet Labs was at a dry dock in Huludao Port in the northeastern province of Liaoning.
It comes after the Pentagon warned late last year China's navy was pressing ahead with plans to build a new attack submarine with vertical launch tubes for cruise missiles.
Professor John Blaxland, from the Australian National University’s Strategic and Defence Studies Centre, told Yahoo News Australia the satellite image of the vessel was not surprising at all, with China's military growth at an "accelerated pace" in recent years.
"The effort to enhance their [military] capability and refine or expand them is consistent with the pattern of behaviour we've been witnessing for five or so years," he said.
"It's exactly what's driven the kind of concerns about Australia needing to double down on its own capabilities, not only in terms of making [Australian submarines] more capable, but having more of them and more rapidly acquiring them."
Prof Blaxland said he did not believe Australia's AUKUS pact, made with the UK and US that will bring nuclear-powered submarines to South Australia, was a motivator behind a possible expansion of China's submarine arsenal.
"[AUKUS] would have been an incidental blip in their consciousness. This has been something they've been working on. China has been down this path now for several years and we are playing a belated catch-up."
Rare satellite image keeps the West on alert
The satellite image shows greenish covers shroud areas behind the submarine's superstructure and stern – parts of the vessel that could house missile launch tubes and a new, quieter propulsion system, analysts said. Such clear images of submarines in dry dock are seldom seen.
The submarine was out of the water between April 24 and May 4, and was later seen mostly submerged in the same place after the dry dock was flooded.
Singapore-based security scholar Collin Koh said there was a great deal of interest in the prospect of a new class of Chinese Type 093 "hunter-killer" submarine, but could not categorically assert whether the images showed a refit or an entirely new submarine.
Jeffrey Lewis, a professor in arms control at the Middlebury Institute of International Studies at Monterey, said a new class of vessel is "plausible" but more questions needed answers to determine whether that was the case.
The Morrison government has repeatedly expressed its concern over China's rapid military growth, with Defence Minister Peter Dutton warning a war in the region involving Australia cannot be ruled out.
China has militarised multiple islands in the South China Sea, while Beijing's controversial security deal with the Solomon Islands has further strengthened China's territorial position, several Australian-based experts have warned.
Both China and Solomon Islands have denied the pact would bring a Chinese military base to the island nation, accusing Australia of paranoia and hypocrisy over the deal.
China's foreign ministry has slammed Australia for its AUKUS deal, saying Canberra had abandoned its commitment to curb nuclear proliferation.
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