Liu Jianchao (second right), China's assistant foreign minister, shakes hands with Japanese Deputy Foreign Minister Shinsuke Sugiyama (second left) during a meeting in Tokyo, Japan on Thursday. Liu Tan/Xinhua/Landov hide caption

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President Obama speaks at a joint news conference with Japan's Prime Minister Shinzo Abe in Tokyo on Thursday. Obama reinforced the U.S.-Japan security commitment. Junko Kimura-Matsumoto/AP hide caption

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A ceremony is held to mark a new patrol vessel in service for China's marine surveillance in Zhoushan, east China's Zhejiang Province, last month. Shen Lei/Xinhua/Landov hide caption

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Concerns over China's air defense claims led Secretary of Defense Chuck Hagel to call Japan's defense minister Wednesday. Here, a man makes a call near a replica of a Chinese fighter jet displayed in Beijing Wednesday. Ng Han Guan/AP hide caption

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Two U.S. B-52s, like the one shown here, have flown through an area that China says is within its air defense zone. China's announcement has irked its neighbors and the U.S. and Japan say they won't abide by it. Andy Rain /EPA/Landov hide caption

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