Unocal Corporation
On August 19, 2003 it was announced that Sinopec, CNOOC, Royal Dutch/Shell and Unocal had entered into a joint venture to exploit the gas reserves in the trough, beginning in mid-2005. Gas production was expected to reach 2.5 km³ a year by 2007. However, on September 29, 2004, the two foreign partners in the joint venture, Royal Dutch/Shell and Unocal Corporation, announced their withdrawal citing doubts over the commercial viability of the resources in the area and the territorial dispute.