Washington: Japan and South Korea flew military aircrafts through a new air defence zone claimed by China, testing the country’s resolve to control a swath of the East China Sea at the heart of a territorial dispute between the nations.

Japan Air Self-Defense Force planes flew through the area without incident as part of patrols that routinely occurred before China established the zone on 23 November, said Japan’s chief cabinet secretary Yoshihide Suga.

“Since China set up its Air Defence Identification Zone, we have been carrying out surveillance activities as usual, including within that zone," Suga told journalists in Tokyo on Thursday.

Tensions are mounting in the region days before US vice president Joe Biden arrives to press Chinese leaders on their intentions with the air zone and to reassure the Japanese government that the US will defend the country if needed under their security alliance. China has urged the US to stay out of the dispute, which centres on overlapping claims to a group of uninhabited islands.

China’s establishment of the zone that includes the islands is a potentially destabilizing unilateral action designed to change the status quo in the region, and raises the risk of misunderstanding and miscalculation, the US defence secretary Chuck Hagel said in a call on Wednesday to Japanese defence minister, Itsunori Onodera, according to an emailed statement by Pentagon spokesman Carl Woog.

Korea flights

Japan’s ruling Liberal Democratic Party said the Chinese air-defence zone is a form of improper expansionism and demanded the country immediately retract the measure, according to a resolution distributed on Thursday.

South Korea’s military sent a plane through the area on 26 November on a regular patrol without notifying China, according to a South Korean military official who asked not to be named discussing military operations. South Korea had flown the aircraft through the area at least twice each week before the announcement of China’s air zone, and would continue to do so, the official said.

China rejected South Korea’s demand to modify its air zone, its defence ministry spokesman, Kim Min Seok, said in a briefing on Thursday. South Korea told China it may expand its own air defence zone, Kim said.

Japanese airlines

The Chinese move also poses a threat to commercial airlines that fly through the region en route to cities across East Asia and raised the specter of Korean Air Lines Co. flight 007. The plane was shot down by jets of the Soviet Union after inadvertently straying into the country’s airspace, killing the 269 people on board.

China signalled on Thursday that it won’t scrutinize commercial aircraft with the same severity as military incursions in the zone. Concerns that air travellers would be at risk rose after Japan told its national carriers not to comply with Chinese demands that they pre-file flight plans before entering the area.

ANA Holdings Inc. ran 27 flights through the area on Thursday without incident. Japan Airlines Co. and Peach Aviation Ltd, a low-fare affiliate of ANA, are also flying through the zone without coordinating with China.

Asked on Thursday if airlines need to report their presence, China’s foreign ministry spokesman Qin Gang said the zone is not targeting normal airlines but since we have put out the notice, we hope airlines will actively cooperate.

B-52 flights

Qin’s comments stood in contrast to the 23 November announcement of the zone carried on the official Xinhua news agency. That report said aircraft flying in the zone should report flight plans to the foreign ministry or its aviation authority.

“This is one of the most serious challenges ever posed by China to freedom of movement both on the sea and in the sky and will affect very seriously the forward deployment of the US," said Tomohiko Taniguchi, an adviser to Japanese Prime Minister Shinzo Abe, in an interview with Bloomberg Television.

“The US sent two unarmed B-52 bombers through the disputed zone this week without advance notice. Predicting that the US will continue to send flights through the area," said Francois Godement, senior policy fellow at the European Council on Foreign Relations. “What they are doing is dropping their business card."

HMS daring

The perils of in-air confrontations are illustrated by a 2001 incident when a Chinese fighter jet collided with a US Navy plane monitoring Chinese communications over the South China Sea. The Chinese pilot was killed, while the US plane made an emergency landing on China’s Hainan Island. China held its crew of 24 for 11 days before freeing them after the US expressed regret for the death of the Chinese pilot.

The risk of shots being fired in a Japan-China dispute over the islands is a no-kidding threat to growth and confidence in the region, Robert McNally, former senior director for international energy on National Security Council, said in a phone interview on Wednesday.

The Chinese move has also focussed attention on military movements in the area. The HMS Daring, a British aircraft carrier, will make a stop in Tokyo next week on its return from the Philippines where it provided typhoon relief. China’s first aircraft carrier, the Liaoning, passed through the Taiwan Strait on Thursday, Xinhua reported, as it heads for exercises in the South China Sea, scene of a territorial spat with the Philippines over the Scarborough Shoal, a rich fishing area.

Island spat

“If China were to attempt a similar defence zone in that area, that would be a significant problem for all of the claimant states in the South China Sea because there’s this threat that China will control the air space," said Albert del Rosario, foreign affairs secretary of the Philippines, in an interview with ABS-CBN news channel on Thursday.

The air defence zone marks the latest escalation between the world’s second and third-largest economies over islands—known as Senkaku in Japanese and Diaoyu in Chinese—located in the zone. More than a year since Japan infuriated China by buying some of the islands from a private owner, planes and ships from the two countries have frequently tailed each other in the area.

The US and Japan last month set out a road map for their alliance over the next 20 years, agreeing to revise the guidelines for defence cooperation for the first time since 1997. The US is compelled to come to Japan’s aid in the event of a conflict.

In Wednesday’s call, Hagel commended Japan for exercising appropriate restraint in response to China’s actions, according to the statement. He reaffirmed the US policy that the US-Japan mutual defence treaty applies to the disputed islands and pledged to consult closely with Japan on efforts to avoid unintended incidents. Bloomberg

Regina Tan and Nicholas Wadhams in Beijing, Benjamin Haas and Andrew Davis in Hong Kong, Sam Kim in Seoul, Mary Schlangenstein in Dallas, Peter S. Green in New York and Norman P. Aquino in Manila contributed to this story.

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