Indonesia–Malaysia confrontation become self-governing in 1959). In May 1961, the UK and Malayan governments proposed a larger federation called Malaysia, encompassing the states of Malaya, North Borneo, Sarawak, Brunei, and Singapore. Initially, Indonesia was mildly supportive of the proposed Malaysia, although the PKI (Partai Komunis Indonesia — Indonesian Communist Party) was strongly opposed to it. In Brunei, it was unclear whether the Sultan Omar Ali Saifuddien III would support Brunei joining the proposed Malaysian state because of the implied reduction of his political office, and Brunei's oil revenues ensured Brunei's financial viability were it to choose independence. Furthermore, a Brunei politician, Dr.
Brunei–Malaysia border goes a further 44 km to the Teraja Hills. From there, the border runs along the watershed between the Belait and Tutong rivers on one hand, and the Baram and Limbang rivers on the other hand. It then proceeds along the watershed of the Brunei and Limbang river basins, enters and runs along Sungai Mendaun, Sungai Melais and Sungai Menunggul (Menunggol) until its estuary at Brunei Bay. The land border between Malaysia and Brunei's Temburong District (which is separated from the other part of Brunei) starts at the estuary of the Pandaruan River and runs the entire length of the