withdrawal was contingent upon the progress of pacification in Cambodia and upon the ability of the KPRAF to contain the insurgent threat without Vietnamese assistance. Prime Minister Hun Sen declared in a May 1987 interview that "if the situation evolves as is, we are hopeful that by 1990 all Vietnamese troops will be withdrawn ... [but] if the troop withdrawal will be taken advantage of, we will have to negotiate to take appropriate measures...." Shortly thereafter, a KPRAF battalion commander told a Phnom Penh press conference that "Vietnamese forces could remain in Cambodia beyond 1990, if the Khmer Rouge resistance continues to pose a threat." In an interview with a Western correspondent, Vietnamese Foreign Minister Nguyen Co Thach repeated the 1990 withdrawal pledge, insisting that only foreign military intervention could convince Hanoi to change its plans. Some ASEAN and Western observers greeted declarations of a total pullout by 1990 with incredulity. Departing Vietnamese units reportedly left equipment behind in Cambodia, and it was suggested that they easily could return if it looked as though a province might be lost. Vietnam's presence in Cambodia reportedly consumed 40 to 50 percent of Hanoi's military budget. Although substantial portions of the cost had been underwritten by Soviet grant aid, Vietnamese troops in Cambodia apparently were on short rations. Radio Hanoi reportedly commented on troops "dressed in rags, puritanically fed, and mostly disease ridden." The parlous state of Vietnamese forces in Cambodia also was the subject of a report by the director of an Hanoi military medical institute. According to media accounts, the report acknowledged that Vietnamese troops in the country suffered from widespread and serious malnutrition and that beriberi occurred in epidemic proportions. Vietnamese military advisers also were detached to serve with KPRAF main and provincial forces down to the battalion, and perhaps even the company, level. The functions and the chain of command of these advisers remained unknown, except that it could be assumed that they reported to the Vietnamese military region or front headquarters. 21st century military structure As a member of ASEAN's defensive program, Cambodia's army has adopted modern military doctrines which call for developing practical co-operation in a regional defense concept. All common branches of military service are maintained and equipped accordingly. Personnel and recruitment figures are centrally administered and published annually. Active combat forces are supported by reserve troops. References Tatu, Frank. "National security". Cambodia: A Country Study