The Norwegian oil company Statoil announced on Friday the discovery of a major gas deposit with its US partner ExxonMobil off the coast of Tanzania. With an estimated 360 million to 540 million barrels of oil equivalent (boe), the find -- the fifth on the same bloc -- brings the size of the discovery to between 3.08 and 3.6 billion boe, the company said in a statement. Tanzania is one of the biggest growth regions for Statoil which faces falling reserves in the North Sea. The company has a 65-percent stake in the bloc, along with ExxonMobil which has 35 percent.