Blue-chip oil major BP has said it will invest $916m (£733m) in gas exploration in West Africa through a partnership with American firm Kosmos Energy.
BP will take a 62 per cent interest in Kosmos' exploration blocks in Mauritania and a 32.5 per cent working interest in its Senegal blocks.
The 33,000 square km of acreage covered by the agreement holds "world-class deepwater gas discoveries", BP has said, including the Tortue field, which is estimated by Kosmos to contain more than 15 trillion cubic feet (tcf) of discovered gas resources.
The total area could contain around 50tcf of gas and more than 1bn barrels of liquid gas.
The agreements are expected to close by the final quarter of next year, subject to government approvals.
BP chief executive Bob Dudley said:
BP’s entry into Mauritania and Senegal represents an exciting strategic opportunity to work with Kosmos Energy in an emerging world-class hydrocarbon basin.
We believe our expertise in integrating the gas value chain, together with a talented exploration partner in Kosmos, along with the support of the Mauritanian and Senegalese governments brings together all the elements needed to create a new liquid natural gas hub in Africa.