China has released a list of Chinese names for 50 new underwater features in the East China Sea, heightening tensions at the same time as an exercise between the United States and Japan in the South China Sea.
China and Japan have a long-running territorial dispute over the Senkaku Islands, which China calls the Diaoyu Dao. The uninhabited islets sit in the deep south of the East China Sea, and are a recurring flashpoint between the two countries.
China's Ministry of Natural Resources published a list identifying and locating 50 undersea features near the Senkakus late Tuesday, similar to its announcement in late April of 55 new undersea features in the South China Sea – most of which were in the exclusive economic zone of another neighbor, Vietnam, and appear to match the location of previous Chinese survey ship activity in the area.
Tensions between China and Japan have ratcheted up in recent weeks. A Chinese submarine was spotted near Amami Oshima Island, inside the 24 nautical mile boundary known as the contiguous zone, by the Japanese Maritime Self-Defense Force (JMSDF) on June 18, according to a press release from Japan's Ministry of Defense.
On the surface, the Japanese Coast Guard released data Monday showing China has maintained a constant presence around the Senkakus since mid-April, and the number of Chinese government vessels and coastguard ships entering Japanese waters throughout 2020 have reached a record high. Altogether, Chinese government vessels have crossed into the Senkakus’ contiguous zone 495 times since Jan. 1, according to Janes, an information company specializing in defense and national security.
Meanwhile, the U.S. Navy 7th Fleet conducted a bilateral exercise Tuesday with close ally Japan in the South China Sea.
"The opportunity to operate with our friends and allies at sea is incredibly important for our combined readiness and partnership," said Rear Adm. Fred Kacher, in a statement released by the 7th Fleet. "Executing complex maritime skills with our Japan Maritime Self-Defense Force allies allows both of our teams to build on our interoperability and readiness as we maintain a free and open Indo-Pacific."
The exercise involved the USS Gabrielle Giffords, a littoral combat ship that has sailed repeatedly in the South China Sea in recent weeks, and two JMSDF training vessels. The drill focused on bilateral communications and precision maneuvering, according to the statement, which said the goal was to build interoperability between the U.S. Navy and the upcoming cohort of Japanese naval officers.
It’s unclear whether the U.S.-Japan exercise prompted China to announce the naming of the 50 new undersea features. China listed 80 new features – including the 55 undersea ones -- in the South China Sea in April in an apparent effort to strengthen its claim over the area and show off its knowledge of the undersea topography in the disputed waters.
While China has claimed “historic rights” to the waters and seabed of the South China Sea, a position never upheld by international law, it has not made the same claim to the East China Sea. Regardless, an International Court of Justice case from 2001 ruled that the name of an undersea feature has no basis when determining sovereignty or territorial claims to the seabed.