 Bulgaria hosted six KC @-@ 135 Stratotanker aircraft and 200 support personnel for the war effort in Afghanistan in 2001 , which was the first stationing of foreign forces on its territory since World War II . International military relations were further expanded in April 2006 , when Bulgaria and the United States signed a defence cooperation agreement providing for the usage of Bezmer and Graf Ignatievo air bases , the Novo Selo training range , and a logistics centre in Aytos as joint military training facilities . The same year Foreign Policy magazine listed Bezmer Air Base as one of the six most important overseas facilities used by the USAF due to its proximity to the Middle East . A total of 756 troops are deployed abroad as part of various UN and NATO missions . Historically , Bulgaria deployed significant numbers of military and civilian advisors in Soviet @-@ allied countries , such as Nicaragua and Libya ( more than 9 @,@ 000 personnel ) . 
