(CNN) -- Tensions magnified among the world's top three economies over China's controversial new air defense zone. The issues range from disagreements on air space as well as disputed islands between China and Japan. On Saturday, China declared the creation of an air defense identification zone in the East China Sea, eliciting strong criticisms from the United States and its close ally, Japan. Both countries refuse to recognize China's newly created zone. What is China's "Air Defense Identification Zone"? China released a map and coordinates that identify its air defense zone on November 23. It declared that aircraft in the area must report their flight plans to China, maintain two-way radio and clearly mark their nationalities on the aircraft. The new rules went into effect 10 a.m. that day, Xinhua reported.
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NEW: U.S. flies 2 B-52s over China's new air defense zone
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China's declaration of air defense zone prompts outcry
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Japan and China's compete with claim for Diaoyu/Senkaku Island
As defined by @placeholder's announcement, the air defense zone's requirements appear to apply to all aircraft.