United Malays National Organisation
The Philippines and Indonesia strenuously objected to this development, with Indonesia claiming Malaysia represented a form of neocolonialism and the Philippines claiming Sabah as its territory. The United Nations sent a commission to the region which approved the merger after having delayed the date of Malaysia's formation to investigate. Despite further protests from the Indonesian President, Sukarno, the formation of Malaysia was proclaimed on 16 September 1963. Indonesia then declared a "confrontation" with Malaysia, sending commandos to perform guerilla attacks in East Malaysia (Sabah and Sarawak). The confrontation was ended when a military coup replaced Sukarno with Suharto. The Philippines, which had withdrawn diplomatic recognition from Malaysia, also recognised Malaysia around the same time.
Sabah
The earliest human settlement in Sabah can be traced back to 20,000–30,000 years ago along the Darvel Bay area at the Madai-Baturong caves. The state had a trading relationship with China from the 14th century AD. Sabah came under the influence of the Bruneian Empire in the 14th–15th century while the eastern part of the territory fell under the influence of Sultanate of Sulu between the 17th–18th centuries. The state was subsequently acquired by the British-based North Borneo Chartered Company in the 19th century. During World War II, Sabah was occupied by the Japanese for three years. It became a British Crown Colony in 1946. On 31 August 1963, Sabah was granted self-government by the British. Following this, Sabah became one of the founding members of the Federation of Malaysia (established on 16 September 1963) alongside Sarawak, Singapore (expelled in 1965), and the Federation of Malaya (Peninsular Malaysia or West Malaysia). The federation was opposed by neighbouring Indonesia, which led to the Indonesia–Malaysia confrontation over three years along with the threats of annexation by the Philippines, threats which continue to the present day.