ROK Air Defense Identification Zone [KADIZ]

While military planes are generally expected to notify a country when entering its ADIZ, these areas are not considered the country’s sovereign air space under international law. China unilaterally proclaimed an ADIZ in the East China Sea on Nov. 23, 2013, which was protested by Seoul, Tokyo and Washington. China’s newly proclaimed ADIZ overlaps Korea’s and Japan’s at points where the countries have disputes over claims, such as Ieodo. Korea responded by expanding its own ADIZ to include Ieodo, which it effectively controls, in December 2013. South Korea and Japan have a system of alerting the other side before planes fly into overlapping ADIZs. However, South Korea does not have a similar setup with China.

Chinese military aircraft entered Korea’s ADIZ dozens of times in 2016. They usually enter in the direction of Ieodo. Japan entered South Korea's identification zone more than 440 times in 2016. Both countries' incursions happened near Ieodo, a submerged rock located off the southern coast of Jeju Island, possibly indicating that Ieodo has become a "contested zone" between China and Japan's air forces. Japan routinely notified South Korea in advance of the entries, while China repeatedly ignored such protocol, entering the zone 59 times during 2016.

On 25 November 2013, the South Korean MND summoned Major General Xi Jingming, Chinese defense attaché, and expressed regret at overlapped ADIZ over the East China Sea recently declared by China. Deputy Minister for National Defense Policy Ryu Je-seung expressed regret that ADIZ over the East China Sea declared by China was partially overlapped with KADIZ southwest of Jeju-do, and including Ieo-do as well. Moreover, Deputy Minister Ryu notified Chinese defense attaché Xi Jingming of disapproval, saying that Korea will maintain the jurisdiction over Ieo-do and the nearby zone regardless of the ADIZ setting of China and/or Japan, and China’s ADIZ was declared unilaterally without prior consultation, so that it could not be officially recognized.

Deputy Minister Ryu continued to propose discussion of this issue at the upcoming Korea-China Defense Strategy Meeting on the 28th, saying the action of China should not be the cause of raising tensions in the region, and the Korean government would strengthen necessary efforts for improving mutual trust among countries in the region. A MND-related official said China mentioned making an effort not to misunderstand each other, fully talking over the issue Korea brought out, and reporting it to the Chinese government, so that it could be discussed at this Korea-China Defense Strategy Meeting.

After China announced the East China Sea ADIZ on 23 November 2013, the South Korea navy sent warships to patrol the waters around Suyan Rock on 02 December 2013.

South Korea annouced on 08 December 2013 that it had expanded the country's air defense identification zone (ADIZ) over the East China Sea.

The announced expansion increased the size of South Korea's ADIZ by approximately 66,480 square kilometers (25,670 square miles) and would cover a submerged rock located in the Yellow Sea, 149 km from Marado off Jeju Island, called Ieodo by South Korea and Suyan by China. The rock, submerged at 4.6 meters below sea-level at low tide, cannot be called 'territory', but nonetheless falls inside the competing Exclusive Economic Zone (EEZ) of both China and South Korea.

This was the first time that South Korea had adjusted its ADIZ since it was demarcated in March, 1951. The KADIZ's eastern and western boundaries remain the same as before. The new ADIZ was scheduled to take effect on 15 December 2013.

China expressed regret over the decision of the Republic of Korea (ROK) to expand its air defense identification zone (KADIZ), a Foreign Ministry spokesman said on 09 December 2013. Spokesman Hong Lei made the remarks after the ROK on Sunday announced a southward expansion of the KADIZ, encompassing submerged rocks within the overlapping exclusive economic zones (EEZ) of the ROK and China. Hong said China and the ROK have maintained communication over the establishment of China's ADIZ and the expansion of the KADIZ. The Chinese Foreign Ministry and the Defense Ministry have stated their position to the ROK side the first time and demanded the ROK side cautiously and properly handle the issues, he said. "China is ready to maintain communication with the ROK side in line with the principle of equality and mutual respect," he said.

On 23 July 2019 two Chinese H-6 bombers and two Russian TU-95 bombers followed by a Russian A-50 airborne early warning and control (AEW&C) flew through the South Korean and Japanese Air Defense Identification Zones (ADIZ). The Russian A-50 AEW&C violated South Korean air space on two occasions. This was the first time in 66 years, since the start of the Korean Armistice Agreement, that a foreign military aircraft violated South Korean airspace. South Korea scrambled jets to intercept the planes after entering the ADIZ and fired 360 warning shots and deployed 20 flares at the Russian A-50 AEW&C after it entered South Korean airspace. There was no operational realism for China or Russia to fly early warning and control airplanes and bombers with extended long-range cruise missiles into allied airspace except as a strategic message of unification and symbolic provocation by China and Russia exemplifying their peer competition against the United States and allied Japan and South Korea for influence and power in the region.

"We take a very grave view of this situation and, if it is repeated, we will take even stronger action," South Korean national-security adviser Chung Eui Yong said in a complaint lodged to Nikolai Patrushev, secretary of the Security Council of Russia. South Korea has also summoned Russia's acting Deputy Chief of Mission Maksim Volkov and Chinese Ambassador Qiu Guohong in protest. Japan said on July 23 that it had also scrambled warplanes to intercept Russian and Chinese planes.

Russia's Defense Ministry said it had conducted its first joint long-range air patrol with China in the Asia-Pacific region and that the flight was not aimed at another country. The ministry said that Russia and China's air forces had not violated the airspace of any other countries, and denied any warning shots were fired by South Korean jets. It accused the South Korean aircraft of carrying out dangerous maneuvers. "The South Korean military took tactical action including dropping flares and firing a warning shot," the Defense Ministry statement said.