Dubai is the largest and most populous city in the United Arab Emirates (UAE). It is located on the southeast coast of the Persian Gulf and is the capital of the Emirate of Dubai, one of the seven emirates that make up the country. Abu Dhabi and Dubai are the only two emirates to have veto power over critical matters of national importance in the country's Federal Supreme Council. The city of Dubai is located on the emirate's northern coastline and heads the Dubai-Sharjah-Ajman metropolitan area. Dubai will host World Expo 2020. Dubai emerged as a global city and business hub of the Middle East. It is also a major transport hub forpassengers and cargo. By the 1960s, Dubai's economy was based on revenues from trade and, to a smaller extent, oil exploration concessions, but oil was not discovered until 1966. Oil revenue first started to flow in 1969. Dubai's oil revenue helped accelerate the early development of the city, but its reserves are limited and production levels are low: today, less than 5% of the emirate's revenue comes from oil.