The main causes of the coup were Norodom Sihanouk's toleration of North Vietnamese activity within Cambodia's borders, allowing heavily armed Vietnamese Communist outfits de facto control over vast areas of eastern Cambodia.
Penyebab utama kudeta karena toleransi Norodom Sihanouk terhadap aktivitas Vietnam Utara dalam perbatasan Kamboja, memungkinkan pasukan bersenjata berat Komunis Vietnam dapat de facto mengontrol wilayah Kamboja timur.