During the first six months of 1964, the Malaysia–Indonesia confrontation assumed an increasingly steady pattern of low-intensity guerrilla warfare in the Borneo territories, nurtured by cross-border raiding parties from Kalimantan and defamatory exchanges of propaganda between Kuala Lumpur and Jakarta, all interspersed with flurries of diplomatic activity as intermediaries tried to bring the sides together and an inconclusive and ritualistic set of meetings was staged. By the end of the period, there was still no sign of a settlement in sight, while moves to resolve the conflict had often merely served to stoke up fresh tensions, accusations and intransigence. In the regional context, the war in Vietnam provided an ominous backdrop, as chronic governmental instability in Saigon en-gendered despair in US officials trying to shore up the deteriorating position. In both Washington and Hanoi, escalation of one form or another was under discussion. The Johnson Administration became increasingly convinced that direct action against the north would need to be taken both to restore morale in Saigon and to help stem the flow of supplies fuelling the insurgency, though not before the presidential election in November was safely out of the way. The North Vietnamese, meanwhile, began preparations in the spring of 1964 to despatch regular army units south to augment the guerrilla forces of the National Liberation Front.

Regular troops also became more commonly employed by Indonesian commanders from early 1964 onwards, though the security forces in the Borneo territories repeatedly demonstrated their prowess over Indonesian intruders in successive engagements during this period and appeared to be well able to deal with the military pressures of confrontation.