Malaysia is the second largest oil and gas producer in Southeast Asia, with proven oil reserves of 3.7 billion barrels and proven natural gas reserves of 38.5 Tcf as of 2013. Its western coast runs alongside the Strait of Malacca, a significant energy corridor linking the Indian and Pacific Oceans, while the eastern part of the nation contains the states of Sabah and Sarawak. Nearly all Malaysia’s oil is produced from offshore fields. These are located on a continental shelf comprising the Malay basin in the west and the Sarawak and Sabah basins in the east. Major companies active in Malaysia’s oil and gas industry are national oil company Petronas, ExxonMobil and Shell.