American bombers and Japanese commercial planes have flown through China’s newly claimed air zone over disputed territories in the East China Sea amid an escalating dispute analysts described as "complex and dangerous."
The flight defiance came as a Chinese naval battle group, including the aircraft carrier Liaoning, sailed to the South China Sea for the first time for a training mission, with the Philippines hitting out at its presence as further fueling tensions over disputed island chains in the area.
The Chinese foreign ministry on Wednesday said the aircraft carrier's voyage via the East China Sea was part of a "normal training arrangement."
Retired Toledo University international politics professor Ran Bogong said Beijing's recent policy in the East and South China Seas showed that the new leadership under President Xi Jinping and Premier Li Keqiang is pursuing a more aggressive foreign policy than that of recent years.
"The Chinese leadership of Xi Jinping and Li Keqiang has decided to drop the policy of hiding [China's] strength and biding its time," Ran said.
"Xi Jinping and the rest are likely to believe that there is no reason for China to do this any more, and that [this] is no longer going to happen," he said.
He said the new policy had increased the danger of confrontation between China and Japan in the East China Sea.
"The dynamics of the situation are very complex, and very dangerous," he said.
But Hong Kong-based military affairs analyst Ma Dingsheng said the Liaoning wouldn't arrive alone in the region, where China has been at loggerheads with Japan over the islands claimed by Tokyo as the Senkaku and by Beijing as the Diaoyu.
"This is a basic naval battle group," Ma said. "When [the Liaoning] sets out, it is always accompanied by its group."
He said the group would consist of destroyers and corvettes.
"There would be no point in it setting out by itself," Ma said.
New air defense zone
China delineated its East China Sea Air Defense Identification Zone over the weekend, warning that Beijing would take "defensive emergency measures" against aircraft that failed to identify themselves properly.
The zone, through which the U.S. B-52 bombers flew through on Tuesday without announcing themselves, is about two thirds the size of Britain, Reuters reported.
Liaoning left its home port of Qingdao in the eastern province of Shandong on Tuesday, according to the official news agency Xinhua.
Just a few hours later, Japan's Defense Minister Itsunori Onodera announced that Tokyo and Washington will "cooperate in responding" to the air defense zone.
Official Chinese media have given prominent online coverage to photos and video of the bombers entering the zone.
Foreign ministry spokesman Qin Gang said China would respond to future incursions with "an appropriate response," depending on the degree of threat perceived by Beijing.
He told a regular news briefing in Beijing on Wednesday that Chinese officials had informed "relevant countries" before setting up the zone, but declined to comment further.
Meanwhile, Tokyo has requested that Japanese airlines stop filing flight plans and other information with Chinese authorities, and aviation officials say there is no threat to passenger safety from this action.
'Driving the US closer to Japan'
Reuters quoted one analyst as saying that Beijing had hope in setting up the zone to erode Tokyo's claim to administrative control over the Diaoyu, or Senkaku.
"This is confirming the darker view of China in Asia," it quoted Brad Glosserman, executive director of the Honolulu-based Pacific Forum CSIS, as saying.
"The Chinese once again are proving to be their own worst enemy ... driving the U.S. closer to Japan and [South] Korea closer to the position of Tokyo as well," he said.
China's 'unilateral action'
Meanwhile, newly arrived U.S. Ambassador to Japan Caroline Kennedy has hit out at the zone as a form of "unilateral action" from Beijing that could undermine regional security.
She also praised Tokyo for showing "great restraint."
"We encourage Japan to increase communication with its neighbors and continue to respond to regional challenges in a measured way," Kennedy said.
Under its treaty with Japan, Washington recognizes Tokyo's administrative control over the Senkakus and is bound to defend Japan in the event of an armed conflict.
But the U.S. has avoided taking an official position on sovereignty claims over the territory.
"We have conducted operations in the area of the Senkakus. We have continued to follow our normal procedures, which include not filing flight plans, not radioing ahead and not registering our frequencies," Pentagon spokesman Colonel Steve Warren said following the flight.
The new rules issued by Beijing state that aircraft should report flight plans to China, maintain radio contact, and reply promptly to identification inquiries.
They should also bear clear markings of their nationality and registration.
U.S. Vice-President Joe Biden is scheduled to travel to Japan next week, as well as to China and South Korea.
Reported by Yang Jiadai for RFA's Mandarin Service. Translated and written in English by Luisetta Mudie.