The tripartite CGDK opposed both the Vietnamese military presence in Cambodia and the government of the People's Republic of Kampuchea that had been installed in Phnom Penh by Hanoi. Each component of the coalition maintained its own force of armed combatants (see fig. 13). Divided by deep-seated animosities among their leaders, these three distinctive and autonomous military forces were brought into a reluctant and uneasy coalition as a result of diplomatic activity by the Association of Southeast Asian Nations (ASEAN). The common goal of contesting the Vietnamese occupation, however, could not bridge the noncommunist coalition partners' deep suspicion toward the renascent Khmer Rouge. Throughout the 1980s, the three combatant forces remained unintegrated, and each maintained separate bases, command structures, and operational planning. An effort by ASEAN to unite the three resistance forces on the Thai border resulted, in May 1984, in the creation on paper of the Permanent Military Coordinating Committee, which apparently never functioned.

Limited tactical cooperation, however, occasionally was reported among the various coalition partners. In one rare example, the three forces participated jointly in a major operation in Batdambang Province in early 1986. Usually, Khmer Rouge units, under their shadowy zonal commanders, remained aloof from their coalition partners and, on occasion, even attacked their military forces and inflicted casualties. Such interfactional clashes were the subject of several complaints by Sihanouk, who charged over the years that Khmer Rouge guerrillas had "repeatedly ambushed and killed [his] troops." These allegations were the principal reason why he chose to step down from the presidency of the CGDK on a leave of absence in May 1987.

Data as of December 1987