The island of Natuna located in the north-eastern part of the province is home to the largest natural gas field in Indonesia (estimated to 1.3 billion m3). The field was discovered in 1973 by Agip. In 1980, the Indonesian state-owned oil company Pertamina and Exxon formed a joint venture to develop Natuna D-Alpha. However, due to the high content the partnership was not able to start production. In 1995, the Indonesian government signed a contract with Exxon but in 2007, the contract was terminated. In 2008, the block was awarded to Pertamina. The new agreement was signed between Pertamina and ExxonMobil in 2010. Correspondingly, the field was renamed East Natuna to be geographically more precise. In 2011, the principal of agreement was signed between Pertamina, ExxonMobil, Total S.A. and Petronas. In 2012, Petronas was replaced by PTT Exploration and Production. As of 2016, negotiations about the new principal of agreement have not finalized and consequently, a production sharing contract is not signed. The area around the gas field is currently disputed between Indonesia and China.