An aerial photo of Uotsuri Island, one of the disputed Senkaku Islands, also known as the Diaoyu Islands, on September 7, 2013.

Story highlights

China releases a map and coordinates that identify its "Air Defense Identification Zone"

The zone includes disputed islands -- known as Senkaku by Japan and Diaoyu by China

China began air patrols over the zone on Saturday

Defense Secretary Chuck Hagel called the move is an attempt to destabilize the status quo in the region

CNN  — 

The United States warned Saturday that China’s military claim to airspace over a disputed island chain creates the risk of “misunderstanding and miscalculation.”

The creation of an “Air Defense Identification Zone” by China, which its top defense official described as an early-warning system, comes amid rising tensions between China and Japan over claims to the islands that are believed to have large oil reserves.

“This unilateral action constitutes an attempt to change the status quo in the East China Sea. Escalatory action will only increase tensions in the region and create risks of an incident,” U.S. Secretary of State John Kerry said.

China has told the United States to butt out of a territorial dispute with Japan in the East China Sea after Washington warned that a military claim by Beijing to airspace in the region raises the risk of “misunderstanding and miscalculations.”

China's 'air defense identification zone'

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The dispute over the islands – known as the Senkaku Islands by Japan and the Diaoyu Islands by China – has strained relations between the two East Asian countries. The islands are close to strategically important shipping lanes and their surrounding waters are full of rich marine life.

The Chinese defense ministry said the new air zone was not directed toward a specific country. But it released a map and coordinates that show the zone covers most of the East China Sea, as well as the islands.

And it warned that its armed forces “will adopt defensive emergency measures to respond to aircraft that do not cooperate in the identification or refuse to follow the instructions.”

The Chinese defense ministry has said it began patrols of the air zone on Saturday.

Japan’s defense ministry said two Chinese planes came within miles of its airspace, prompting authorities to scramble Japanese fighter jets.

It’s the second time this month that Japan has launched fighter jets, alleging Chinese planes appeared to be closing in on its air space.

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U.S. Secretary of Defense Chuck Hagel called the move by China an attempt to destabilize the status quo in the region, saying it “increases the risk of misunderstanding and miscalculations.”

“This announcement by the People’s Republic of China will not in any way change how the United States conducts military operations in the region,” Hagel said.

The long-running disagreement over who owns the islands intensified between Japan and China in the second half of 2012.

Protests erupted in China after Japan announced it had bought several of the disputed islands from private Japanese owners. The deal was struck in part to prevent the islands from being bought by the controversial Tokyo governor Shintaro Ishihara, who had called for donations for a public fund to buy them.

READ: Asia’s disputed islands – who claims what?

China was outraged, as were groups of its citizens who protested violently in several Chinese cities, calling for boycotts of Japanese products and urging the government to give the islands back.

In December 2012, the dispute escalated further when Japan scrambled fighter jets after a Chinese plane was seen near the islands. That situation has recurred repeatedly since, and China’s latest announcement makes it likely it will keep happening.

China says its claim extends back hundreds of years. Japan says it saw no trace of Chinese control of the islands in an 1885 survey, so formally recognized them as Japanese sovereign territory in 1895. Japan then sold the islands in 1932 to descendants of the original settlers.

The Japanese surrender at the end of World War II in 1945 only served to cloud the issue further.

The islands were administered by the U.S. occupation force after the war. But in 1972, Washington returned them to Japan as part of its withdrawal from Okinawa.

Taiwan, which Beijing regards as a breakaway province, also lays claim to the islands.

CNN’s Barbara Starr and Tom Dunlavey contributed to this report.