During the Kosovo War, the German Air Force participated for the first time since the Second World War in an armed combat mission as part of Operation Allied Force (OAF), which lasted from March 24 to June 10, 1999. Following the ceasefire agreement on June 9, 1999, NATO forces entered Kosovo on June 12, 1999, following a resolution by the United Nations Security Council, which regulated the deployment of the NATO Kosovo Force (KFOR-Kosovo Force). It initially included about 8,000 German troops and was established to monitor the withdrawal of Serbian troops and the demilitarization of Kosovo following the Kosovo War. Gerhard Schröder (SPD), who was elected Chancellor the year before, visited German troops in Kosovo in July of 1999. Operation Allied Force was the first NATO operation that was neither covered by a UN mandate nor justified by invoking alliance solidarity and remains controversial until today. The Bundeswehr still maintains a small presence in Kosovo.