Putting up a brave face, China's Defence Ministry said it "detected, identified and monitored" the flight of the giant long-range Stratofortress planes that flew the zone between two different times on Tuesday night.
"The Chinese government has the will and ability to defend our national sovereignty and security," foreign ministry spokesman Qin Gang said at a press briefing.
"We also have the ability to exercise effective control over the East Sea Air Defence Identification Zone," he said. Defence Ministry spokesman Geng Yansheng said the US aircraft skirted along the border of the zone and flew in the north-south direction, 200 kilometres east of DiaoyuIsland.
China calls the disputed islands Diaoyus while Japan terms them as Senkakus.
Under the rules of the new air zone, all aircraft including the civilian flights have to report their flight plans to China, must maintain the two-way radio communications and respond in a timely and accurate manner to identification inquires.
Those that do not comply can face "defencive emergency measures", Beijing said.
The US along with Japan refused to accept the zone announced by China over the disputed islands administered by Japan.
The Pentagon said it did not comply with Beijing's controversial demand for aircraft to file flight plans when traversing the East China Sea area. United States Colonel Steve Warren at the Pentagon said Washington had "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," Warren said.
China's defence spokesman Geng said: "The Chinese military monitored the entire process, carried out identification in a timely manner, and ascertained the type of US aircraft.
"We need to stress that China will identify every aircraft flying in the air defence identification zone according to the country's announcement of aircraft identification rules for the air defence identification zone.”
Answering a spate of questions on what China will do in view of provocative moves by the US and a very defiant stance by Japan that it would not recognise the zone, Qin tried to dispel the perception that China appeared as a "paper tiger" in the face of such assertive moves.
"The term paper tiger has its own specific meaning. You can check why Chairman Mao said paper tigers," he shot back reminding how Mao Zedong branded imperialists as paper tigers during 1950s.
Asked whether China would enforce such a zone along the India-China border and South China Sea, Qin drew the attention of the Defence ministry spokesman's comments that "China will establish other air defence identification zones at an appropriate time after completing preparations".
Observers said air defence zones are established for coastal areas which have 12 nautical mile territorial waters but not around the land borders.
If the East China Sea zone is successful, China may consider applying the same to the disputed South China Sea as it claims most of it.
China announced the new air defence zone on November 23. The zone drew flack from South Korea and Australia besides the US and Japan.
The US which has a security treaty with Japan where over 70,000 American troops were stationed was emphatic that it would not respect the Chinese zone. The American stance leaves China few options as either it has to back down or confront the US military to strictly enforce its authority over the zone.
Also China had to contend with new set of naval exercises by the US and Japan from tomorrow, which according to the state television here would take place almost on the fringes of air zone.
In view of this, more US violations were expected to take place. Defending China's move to declare the air zone as legitimate move, Qin said China had informed "relevant countries" before it was announced. He, however, declined to identify the countries whom China has informed.
Image: A group of disputed islands, Uotsuri island (top), Minamikojima (bottom) and Kitakojima, known as Senkaku in Japan and Diaoyu in China is seen in the East China Sea, in this photo taken by Kyodo.
Photograph: Kyodo/Reuters
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