Japan's Foreign Ministry said Friday it has confirmed ongoing construction by China of a facility believed to be meant for unilateral gas field development in the East China Sea.
The ministry lodged a protest with the Chinese Embassy in Tokyo, saying it is regrettable that China has pushed forward with unilateral development.
Japan and China agreed on joint gas development in the area in 2008, but negotiations were suspended in 2010.
Including the latest facility, Tokyo has been aware of Chinese gas development at 17 locations near the so-called median line between their coastlines, which Japan regards as the demarcation line between the two countries under domestic law. China argues its exclusive economic zone extends much further from the mainland.