Upper Karabakh, or Nagorno-Karabakh, an internationally recognized territory of Azerbaijan, has been under illegal Armenian occupation since 1991.
International organizations, including the UN, have demanded the withdrawal of the occupational forces. The Organization for Security and Cooperation in Europe Minsk Group -- co-chaired by France, Russia and the US -- was formed in 1992 to find a peaceful solution to the conflict, but to no avail.