Japanese officials have revealed that China has been building a new offshore platform near the median line which divides the waters of the two nations.

China is developing gas fields in the region, and has started work on a new offshore platform near Japanese waters. Defense Minister General Nakatani claimed that the platform could represent a security concern, according to Bloomberg.

Japan Worried By China's New Platform In East China Sea

Militarization in the East China Sea

Nakatani believes that Beijing “could install a radar system on the platform, or use it as an operating base for helicopters or drones conducting air patrols.” The move comes amid growing tension in the South China Sea, where China has competing territorial claims with a number of different states.

Beijing has been building artificial islands on top of rock reefs in the Spratly Islands, and one even features a full-length airstrip and communications facilities. Given Chinese actions in the Spratlys, Japan is understandably concerned by a new offshore platform in the East China Sea, which could be militarized.

The East China Sea is subject to regular air patrols by Japan’s Self-Defense Forces and Coast Guard, but neither body specified how many platforms are being built, where they are, or other technical details. Japan claims to have spotted the construction work in June 2013, and despite Tokyo’s request that work be halted, it appears that Beijing has continued to build.

Long-running dispute concerning maritime borders

Japanese Prime Minister Shinzo Abe told a special meeting of the lower house special committee: “I strongly object to (China) repeatedly going ahead with unilateral development.”

Beijing declared an air defense identification zone (ADIZ) in the East China Sea in November 2013, despite the fact that radar on the Chinese mainland does not cover the entire area.

“If radar was installed on the platform, it would supplement the (ADIZ),” Nakatani said. “It would improve China’s capacity for surveillance and warning, which could give them a better idea of the SDF’s activities.”

The maritime borders in the East China Sea are not clearly demarcated, although a line has been drawn which runs halfway between the coastlines of the two nations. The platform is situated on the Chinese side of that line, but its development is worrying for Japan.

Gas fields cause headaches

Unilateral Chinese development of gas fields in the area was first discovered in 2004, at Shirakaba (Chinese name: Chunxiao), Kashi (Tianwaitian), Asunaro (Longjing) and Kusunoki (Duanqiao). In June 2008, Japan and China reached an agreement on a joint development region for waters which are next to the midline, as well as working together on the Shirakaba field, which is on the line.

Although talks concerning the other fields are still underway, there has been little progress in reaching an agreement.

Japan has become increasingly worried by China’s aggressive behavior in the South China Sea. Prime Minister Shinzo Abe has expressed a desire to loosen strict rules governing the activities of the Self-Defense Force, which were imposed in a pacifist constitution in the aftermath of World War II.

Considering that the government was considering such an historic change due to Chinese activities far from Japanese shores, it is understandable that the alarm has been raised by Chinese encroachment in waters which are considered to be Japanese.

Relations strained between Japan and China

Tokyo previously expressed a desire to set up patrols of the South China Sea, a move which would see it join the U.S. in patrolling an area of growing geopolitical concern. Although Japan cannot engage in such activities unless certain laws are relaxed, the news provoked a strong response from China, which warned Japan to stay out of a dispute in which it has no direct claim.

The two nations are also embroiled in a long-running dispute over the Senkaku/Diaoyu islands, and Japan appears to be concerned by China’s increasingly aggressive rhetoric. Japan relies on the free passage of ships to ensure that it can trade with the outside world, and Chinese control of the South and East China Seas is not a comfortable thought.

China’s maritime activities appear to be one way in which Beijing is pushing for greater authority in Asia. It has asked for greater respect and recognition for its place in the world order, and is challenging U.S. primacy in the region. Washington so far has not found a way of deterring Beijing from pursuing its land reclamation programs in the South China Sea, and the new platform in the East China Sea provides another headache for U.S. officials.

Although the U.S., Japan and other regional allies are increasingly working together to counteract China, the fact remains that Chinese forces are particularly well-adapted for conflict near the country’s coastline. A conflict in the region is not one which the U.S. and its allies are guaranteed to win.