today one of the seven emirates that comprise the United Arab Emirates, was not recognised as a Trucial State until 1952. Kalba, recognised as a Trucial State by the British in 1936 is today part of the emirate of Sharjah. Until 1930's, the British refrained from interfering in the internal affairs of the Trucial Sheikdoms as long as the peace was kept in contrast to their policy in Oman where they were concerned on maintaining stability of Oman's Sultanate and were eager to maintain their airbase in Masirah Island. According to a British official: Discovery of oil In the 1930s, the first oil company teams carried out preliminary surveys. An onshore concession was granted to Petroleum Development (Trucial Coast) in 1939, and an offshore concession to D'Arcy Exploration Ltd in 1952. Exploration concessions were limited to British companies only following the conclusion of agreements with the Trucial Sheikhs and British government. Management of the Trucial Coast moved from the British Government in Bombay to the Foreign Office in London in 1947, with Indian independence. The Political Resident in the Gulf headed the small team responsible for liaison with the Trucial Sheikhs and was based in Bushire until 1946, when his office was moved to Bahrain. Day-to-day management of affairs was carried out by the 'Native Agent', a post established with the 1820 treaty and abolished in 1949. This agent was bolstered by a British Political Officer based in Sharjah, from 1937 onwards. Oil was discovered under an old pearling bed in the Persian Gulf, Umm Shaif, in 1958, and in the desert at Murban in 1960. The first cargo of crude was exported from Jabel Dhanna in the Emirate of Abu Dhabi in 1962. As oil revenues increased, the ruler of Abu Dhabi, Sheikh Zayed bin Sultan Al Nahyan, undertook a massive construction program, building schools, housing, hospitals and roads. When Dubai's oil exports commenced in 1969, Sheikh Rashid bin Saeed Al Maktoum, the ruler of Dubai, was also able to use oil revenues to improve his people's quality of life. Buraimi dispute In 1952 a group of some 80 Saudi Arabian guards, 40 of whom were armed, led by the Saudi Emir of Ras Tanura, Turki Abdullah al Otaishan, crossed Abu Dhabi territory and occupied Hamasa, one of three Omani villages in the Oasis, claiming it as part of the eastern Province of Saudi Arabia. The Sulṭan of Muscat