The exclusive economic zone of North Korea stretches 200 nautical miles from its basepoints in both the Yellow Sea and the Sea of Japan. The exclusive economic zone (EEZ) was declared in 1977 after North Korea had contested the validity of the Northern Limit Lines (NLL) set up after the Korean War as maritime borders. The EEZ has not been codified in law and North Korea has never specified its coordinates, making it difficult to determine its specific scope. In the Yellow Sea, the EEZ remains unspecified in the Korean Bay because China has not determined its own EEZ in the area. The border between the North Korean and South Korean EEZs in the Yellow Sea cannot be determined because of potential overlap and disputes over certain islands. In the Sea of Japan, the North Korean EEZ can be approximated to be trapezoidal-shaped. The border between North Korea and Russia's respective EEZs is the only such border that has been determined in Northeast Asia. Here, the EEZ does not cause many problems, even with regards to South Korea, because the sea is not thought to be rich in natural resources. History The Korean Armistice Agreement specified a Military Demarcation Line as a land border between North and South Korea, but failed to determine a maritime border. The United Nations Command of the Military Armistice Commission (UNCMAC), however, unilaterally set two maritime borders, one at the Yellow Sea and one at the Sea of Japan, known as Northern Limit Lines (NLL). Ever since the legal status of the NLLs has been contested and clashes have taken place. In 1973, North Korea explicitly challenged the validity of the Yellow Sea NLL. UNCMAC had accused North Korea of intruding to the south of the NLL, to which North Korea responded by claiming that its maritime boundary lies south of the NLL. On 18 January 1952, South Korean President Syngman Rhee declared a "Peace Line" establishing a wide area of maritime sovereignty around the entire Korean Peninsula, including North Korea, on the basis that this was the legal government for all of Korea. It claimed an area averaging 60 nautical miles from the Korean coast. This claim, generally called the Syngman Rhee Line, was not internationally accepted. On 21 June 1977, North Korea declared an economic zone of 200 nautical miles. The zone became effective on 1 August. That day, North Korea also declared