East Malaysia is 50% bigger than Peninsular Malaysia at , comparable with South Dakota or Great Britain. East Malaysia contains the five highest mountains in Malaysia, the highest being Mount Kinabalu at 4095 m, which is also the highest mountain in Borneo and the 10th highest mountain peak in Southeast Asia. It also contains the two longest rivers in Malaysia – Rajang River and Kinabatangan River. Banggi Island in Sabah and Bruit Island in Sarawak are the two largest islands that are located entirely within Malaysia. The largest island is Borneo, which is shared with Indonesia and Brunei. The second largest island
Indonesia–New Zealand relations Federation of Malaysia as a means of perpetuating British imperialism in Southeast Asia. Sukarno was also sympathetic to the Brunei People's Party's failed revolt in Brunei and was buoyed by the success of Indonesia's "confrontation" policy against Dutch New Guinea and the Philippines reviving its territorial claim to the Malaysian state of Sabah. Throughout the Indonesian-Malaysian Confrontation, Indonesia waged an undeclared border war against Malaysia and sent armed parties on cross-border operations into the East Malaysian states of Sarawak and Sabah, which bordered Indonesia's Kalimantan provinces. In September 1964, Indonesian extended its infiltration operations to peninsular Malaysia. New Zealand agreed