US and Japan join forces to monitor Chinese submarines.

Japan and the United States are cooperating to deploy a submarine detection system in the Nansei Islands region of the Pacific Ocean to counter China's increasing maritime activity.

This latest Sound Surveillance System (SOSUS) will allow Tokyo and Washington to detect Beijing's submarines moving in the East China Sea and Yellow Sea en route to the Pacific Ocean, Kyodo News reported yesterday, citing sources from the Japanese Ministry of Defense and the Maritime Self-Defense Force (MSDF). This is the first time information about the existence of a tracking system specifically targeting China has been revealed.

A Chinese submarine is anchored at Hong Kong's Ngong Shuen Chau naval base. Photo: AFP

Because SOSUS is a "top secret" plan, the MSDF only explains the most important features of this US-developed system to a select few key leaders of the Japanese government, including the prime minister and the defense minister.

Previously, there were reports that Tokyo and Washington had deployed an older version of SOSUS beneath the Tsugaru Strait in northeastern Japan and in the Tsushima Strait in southwestern Japan to detect Soviet submarines during the Cold War.

According to sources, the latest SOSUS system will consist of two cables connecting multiple underwater listening networks. One cable will extend from Okinawa to the south of Kyushu Island, and the other from Okinawa to the waters off Taiwan. Other details, such as when the system will become operational, have not yet been disclosed.

According to VNE