Uganda discovered commercial hydrocarbon deposits in its western region along the border with the Democratic Republic of Congo in 2006 and estimated reserves at 2.5 billion barrels. Production of the oil has not begun, however.

"We have been doing a lot of appraisal work over the last several months on the wells in blocks 1 and 2 and the reserves have been increasing and now we're able to confirm that we have about 3.5 billion barrels in place," Ernst Rubondo, the commissioner for the Petroleum Exploration and Production Department, told Reuters.