Beijing: Japan and South Korea today said their military planes flew through China`s newly declared air defence zone, adding to the international defiance of Beijing after two US B-52 bombers passed through the airspace in the disputed East China Sea.
Japanese aircraft had conducted routine "surveillance activity" over the Air Defence Identification Zone (ADIZ), a Japanese government spokesman said in Tokyo.
South Korea had also conducted a flight, the South Korean defence ministry said in Seoul.
A day earlier two giant US Stratofortress bombers flew through the AIDZ that China unilaterally declared last week.
China demanded that planes transiting the airspace must file their flight plans, declare their nationality and maintain the two-way radio communications -- or face "defencive emergency measures".
The controversial zone includes disputed islands claimed by China, which calls them as the Diaoyus, but controlled by Japan, which terms them as the Senkakus.
Japanese officials did not specify when the flights happened, but confirmed the surveillance activity.
"Even since China has created this airspace defence zone, we have continued our surveillance activities as before in the East China Sea, including in the zone," Japan`s government spokesman, Yoshihide Suga, said.
"We are not going to change this [activity] out of consideration to China," he said.
Under fire from the US and other countries over the ADIZ, Chinese Defence Ministry said it will consider to revoke the zone if Japan which has a similar defence zone withdraws it.
"Should the decision be retracted, we ask the Japanese side to revoke its Air Defence Identification Zone first, we will then consider their demand 44 years later," Defence Ministry spokesman Yang Yujun told reporters.
His comments came in response to Japanese Prime minister Shinzo Abe`s call for China to withdraw the zone.
Japan established its own ADIZ in 1969, therefore it has no right at all to make irresponsible remarks on China`s ADIZ in the East China Sea, state-run Xinhua quoted Yang as saying.
China claimed that besides the US and Japan, 18 other nations have such security zones beyond their coastal waters.
The Japanese zone was extended few times including in 2010 covering the disputed islands. Both Chinese and Japanese ADIZs overlap in the area.
Yang defended the zone saying it is completely justified and legitimate. He refuted Japanese criticism that China had altered the status quo unilaterally by announcing the ADIZ.
Yang reaffirmed China`s commitment to respecting other countries` rights of free flight under international laws.
"The normal flight of international flights in the zone will not be affected," he said, insisting that the establishment of the China`s ADIZ will not change the legal nature of relevant airspace.