Head of state second and last incumbent of the office, Yusof bin Ishak, kept the style at 31 August 1963 unilateral declaration of independence and after 16 September 1963 accession to Malaysia as a state (so now as a constituent part of the federation, a non-sovereign level). After its expulsion from Malaysia on 9 August 1965, Singapore became a sovereign Commonwealth republic and installed Yusof bin Ishak as its first President. In 1959 after the resignation of Vice President of Indonesia Mohammad Hatta, President Sukarno abolished the position and title of vice president, assuming the positions of Prime Minister and Head of Cabinet.
Combat operations in 1965 during the Indonesia–Malaysia confrontation Combat operations in 1965 during the Indonesia–Malaysia confrontation The Indonesia–Malaysia confrontation began in early 1963 following Indonesia's opposition to the creation of Malaysia. In December 1964, a build-up of Indonesian forces on the Kalimantan border saw the British government commit significant forces from the UK-based Army Strategic Command and Australia and New Zealand deployed roulement combat forces from West Malaysia to Borneo in 1965–66. In January 1965, the first UK-based units (aside from air defence and special forces) arrived and after six weeks of jungle training, deployed on operations. The 1st Battalion Gordon Highlanders arrived first and became the thirteenth