On Monday, December 9, Tokyo cautiously gave its approval to South Korea‘s expanded air defense zone, making clear that it was against a similar announcement made earlier by China because it covered territory controlled by Japan. On Sunday, December 8, South Korea had made public an expanded air defense zone, which covers a submerged rock disputed by Beijing and Seoul, and said it would take effect by December 15. Japanese Chief Cabinet Secretary Yoshihide Suga said on Monday that Seoul had informed Tokyo in advance about its plans, something Beijing had failed to do.
“We don’t think it’s going to be a problem at the moment,” Suga told reporters in Tokyo. “It is different from the one announced by China because it does not cover our country’s territorial air, waters or land,” he added. Japan Prime Minister Shinzo Abe had reportedly given Defense Minister Itsunori Onodera a mandate to set up a “thorough system of communication” between Tokyo and Seoul over the expanded zone. Seoul’s announcement of their expanded zone means that the three neighboring countries’ air defense zones now overlap over the Ieodo islands, a submerged reef believed to be rich in natural gas and mineral deposits that is currently under South Korea’s control but is being contested by China.
Regional tensions have been on high alert since Beijing declared an Air Defense Identification Zone (ADIZ) in the East China Sea last month, in which foreign planes are supposed to file flight plans with China. The airspace claimed by China overlaps with the Senkaku Islands, a group of uninhabited isles controlled by Japan which Beijing also claims as the Diaoyus. The US, Japan and South Korea has accused China of unilaterally changing the status quo in the region where tensions are already high, and consequently flew military and paramilitary aircraft into the area in shows of defiance.