British subject (short-lived) incorporation of Singapore within Malaysia between 1963 and 1965. Similar arrangements also existed for the other states and colonies that made make up the Federation of Malaya from 1948: they too introduced citizenship statuses (which eventually became Malayan and later Malaysian citizenship) before achieving independence in 1957. In most other Commonwealth countries, the term Commonwealth citizen was used instead of British subject. On 1 January 1983, upon the coming into force of the "British Nationality Act" 1981, every citizen of the United Kingdom and colonies became either a British citizen, British Dependent Territories citizen or British Overseas citizen. Use
Federation independence from the sovereign state, which only takes care of their foreign relations and defence. However, they are neither considered to be part of it, nor recognised as sovereign or associated states. The distinction between a federation and a unitary state is often quite ambiguous. A unitary state may closely resemble a federation in structure and, while a central government may possess the theoretical right to revoke the autonomy of a self-governing region, it may be politically difficult for it to do so in practice. The self-governing regions of some unitary states also often enjoy greater autonomy than those of