Platform construction in the East China SeaTOKYO, Jun 20 with the completion of a drilling rig in the East China Sea, the Kyodo news agency said. The agency reports that the protest was transmitted to the Chinese side through diplomatic channels.Okinawa to hold first-ever exercise simulating defense against outside attackJapan's maritime security authorities discovered on Monday that drilling equipment has been placed on the rig, so its purpose is beyond doubt. Exactly one month ago, Japan discovered a new gas drilling rig across the dividing line between Japan and China, and protested to China. The PRC is drilling gas fields at installations in the East China Sea in an area where the two countries have not reached a final agreement on the border. Japan believes that the line runs along the border of its exclusive economic zone, China insists that its exclusive economic zone extends to the Okinawa Trench. The drilling rig discovered by Japan in May this year is already the 17th one built by China in the area. Tokyo believes that China is unilaterally developing a gas field that lies on the border between the two countries and is equally claimed by Japan. In 2008, Japan and China agreed to jointly develop fields located in the disputed area, and began to negotiations on a specific embodiment of the agreement. However, after a Chinese fishing trawler collided with a Japanese maritime security vessel near the disputed Senkaku Islands in 2010, negotiations were interrupted by the Chinese side. Japan tracked the movements of Russian and Chinese ships for two days
