Korean War has since been patrolled by the KPA and ROKA, United States, and Joint UN Commands. The Demilitarized Zone runs northeast of the 38th parallel; to the south, it travels west. The old Korean capital city of Kaesong, site of the armistice negotiations, originally was in pre-war South Korea, but now is part of North Korea. The United Nations Command, supported by the United States, the North Korean People's Army, and the Chinese People's Volunteers, signed the Armistice Agreement on 27 July 1953 to end the fighting. The Armistice also called upon the governments of South Korea, North Korea, China and
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