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 line. Malaysia's submission was jointly made with Vietnam where both countries claimed a "defined area" over which both countries currently have overlapping claims. Brunei should also have a competing claim over a portion of the "defined area". However, unlike China and the Philippines which objected to the Malaysia-Vietnam joint submission, there is no record of Brunei registering any similar objection. Brunei has not submitted its extended continental shelf claim to Commission on the Limits of the Continental Shelf. However, in its preliminary submission which it lodged with the Commission on 12 May 2009, it gave notice of its intention to