China Confirmed to Be Operating Drilling Vessel Near Japan-China Median Line

The Yomiuri Shimbun

16:30 JST, January 8, 2026

China has begun operating a mobile drilling vessel on its side of the Japan-China median line in the East China Sea, the Japanese government said Thursday.

The government views the operation, which Japan had confirmed by Jan. 2, as a move by China to develop a new gas field. The Foreign Ministry has lodged a protest with China through diplomatic channels, expressing strong regret over the unilateral development.

The two nations agreed in 2008 to jointly develop part of the gas fields straddling the median line between Japan and China. However, China has suspended negotiations, citing a deterioration in bilateral relations, and continued activities such as building unauthorized structures near the line.

About 20 unauthorized structures that Japan believes to be the foundation of facilities to develop gas fields have been confirmed so far.

“Despite repeated protests from the Japanese side, it is extremely regrettable that [China] continues to carry out unilateral development and attempts to establish a fait accompli in these waters,” Chief Cabinet Secretary Minoru Kihara said at a news conference on Thursday morning.

Japan maintains that gas fields being drilled by China possibly extend to Japan’s side underground, drawing on Japanese resources.