Japan finds itself surrounded by a worsening security environment as North Korea pushes forward with missile development and China and Russia step up military activity in the region, Japan's Defense Ministry said on Tuesday.
The ministry's annual white paper comes after intermittent testing by North Korea of ballistic missiles in defiance of a U.N. ban, and a record number of scrambles by Japanese fighter jets in April-June due to increased flights by Chinese and Russian planes close to Japan's air space.
"With a trend toward arms buildup and modernization, and brisker military activity by neighboring countries getting prominent, security challenges and destabilizing factors for Japan and the rest of the Asia-Pacific are becoming more serious," the ministry said in the paper.
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Prime Minister Shinzo Abe returned to power in December 2012 intent on easing the limits of the post-war pacifist constitution on the military to let Japan play a bigger global security role.
Abe's government this year took some historic steps away from Japan's post-war pacifism by easing weapons export restrictions and ending a ban that has kept the military from fighting abroad.
The moves have been viewed warily elsewhere in Asia, in particular in China. Ties between China and Japan were already strained by a territorial dispute over a group of tiny East China Sea isles as well as rows over the legacy of Japan's wartime aggression. Patrol ships from both countries routinely shadow each other near the islands, stoking fear of clashes.
Recently, however, Abe has renewed a call for a bilateral summit with Chinese President Xi Jinping. The two governments are trying to arrange a summit on the sidelines of a Pacific Rim conference in Beijing in November, the Nikkei newspaper said on Monday.
The ministry's report described China's action in maritime disputes with other countries as "high-handed" and called on China to observe international norms.
China in November launched an air defense identification zone covering a swathe of the East China Sea, including the disputed isles, and warned it would take "defensive emergency measures" against aircraft that failed to identify themselves.