South Korea announced an expanded air defence zone on Sunday that overlaps with a zone that China declared last month, raising tensions in the region.
Seoul’s new air defence and identification zone now takes in a submerged rock in the Yellow Sea that is also inside China’s zone.
Both countries claim the rock, called Ieodo by South Korea and Suyan by China.
South Korea and Japan both were angered when China on November 23 announced its zone, which encroached on Japan’s and South Korea’s.
Seoul and Tokyo complained that China’s action was unilateral and illegitimate.
South Korea has told its commercial airlines not to report to Chinese authorities when they cross China’s zone, and it, along with the United States and Japan, have sent undeclared military aircraft into the zone.
Seoul extended its own zone farther south. The Defence Ministry said the move was made so the zone would coincide with South Korea’s flight information region for civil aviation.
“Ahead of today’s announcement, we have offered sufficient explanations to related countries,” the Defence Ministry said, adding that the expanded zone “does not put restrictions on civilian flight operations or infringe upon the airspace and interests of neighbouring countries.” The new zone takes effect December 15, the ministry said. The change was the first made to the zone since the US military established it in 1951 during the Korean War.
China was reserved in its reaction to South Korea’s announcement at the beginning of the month that it would expand its zone, saying Seoul should observe international law.
The area covered by the countries’ competing defence zones is the focus of bitter, years-long territorial disputes. Beijing’s zone also covers the Japanese-controlled Senkaku islands. The islands, called Diaoyu by China, lie near oil and gas reserves in the East China Sea and are also claimed by Taiwan as the Tiaoyutai.
Beijing’s declaration of its zone was regarded as a reaction to US President Barack Obama’s "pivot" of US foreign and defence policy towards Asia as the US seeks to raise its influence in the region.
It was a key topic for US Vice President Joe Biden during his trip last week to Japan, China and South Korea. He called China’s zone a “unilateral attempt to change the status quo in the East China Sea.” His talks with Chinese President Xi Jinping produced no breakthrough.
South Korea’s announcement was made on the day it began two days of naval manoeuvres with the United States and Britain off its southern coast.
The exercises were not timed to protest China’s air defence zone, said Commander Steven Curry, a spokesman for the US Pacific Fleet.
South Korea and the US regularly hold military exercises on water, land and in the air, primarily to prepare for any threats from North Korea, he said.