Tokyo: Japan's Foreign Ministry on Tuesday confirmed that China is constructing a new structure on the western side of the Japan-China median line in the East China Sea, raising fresh concerns over Beijing's unilateral actions in the contested area. The facility is believed to be part of ongoing resource development efforts by China.

According to Philippines News Agency, Masaaki Kanai, director general of the ministry's Asian and Oceanian Affairs Bureau, lodged a protest with Chinese Embassy official Shi Yong, calling the move 'extremely regrettable,' especially as the maritime boundary between the two nations' exclusive economic zones (EEZs) remains demarcated.

China has been accelerating resource development in the East China Sea, and 20 structures have been confirmed so far. In June 2008, Japan and China agreed to jointly develop resources in the sea, but talks on the matter have since been suspended.