Following these raids the government conceded to British and Malaysian requests to deploy an infantry battalion to Borneo . During the early phases , British and Malaysian troops had attempted only to control the Malaysian / Indonesian border , and to protect population centres . However , by the time the Australian battalion deployed the British had decided on more aggressive action , crossing the border into Kalimantan to obtain information and conduct ambushes to force the Indonesians to remain on the defensive , under the codename Operation Claret . The fighting took place in mountainous , jungle @-@ clad terrain , and a debilitating climate , with operations characterised by the extensive use of company bases sited along the border , cross @-@ border operations , the use of helicopters for troop movement and resupply , and the role of human and signals intelligence to determine enemy movements and intentions .