Northern Limit Line mainland portion reverted to North Korean control, while the islands remained a part of South Korea despite their close proximity. The line extends into the sea from the Military Demarcation Line (MDL), and consists of straight line segments between 12 approximate channel midpoints, extended in an arc to prevent egress between both sides. On its western end the line extends out along the 38th parallel to the median line between Korea and China. The 1953 Armistice Agreement, which was signed by both North Korea and the United Nations Command (UNC), ended the Korean War and specified that the five islands
Soviet Union in the Korean War China. By April 1950, the Soviet Union had provided 63 of the North Korean Air Force's 178 aircraft, which until September 1950 proved highly effective against minimal South Korean air defenses (which was more heavily backed by US and UN air forces instead) An important area in which Soviet intervention was key in the Korean War was in the air-war. Soviet innovation in aircraft design, as well as the experience of many of its pilots following the Second World War meant that the 'new' states of China and North Korea were dependent on Soviet help in this area. Both the