The agreement comes after BP concluded a deal on Saturday that handed a 2 per cent stake to the government of Abu Dhabi.
Under the terms of the deal, BP will acquire a 62-per cent stake and operational control in Kosmos' licenses covering blocks C6, C8, C12, and C13 offshore Mauritania, as well as a 32.49-per cent stake in the licenses covering the Saint Louis Offshore Profond and Cayar Offshore Profond blocks offshore Senegal. Its assets include existing production and development projects offshore Ghana, large discoveries offshore Mauritania and Senegal, as well as exploration licenses with significant hydrocarbon potential offshore Portugal, Sao Tome and Principe, Suriname, Morocco, and Western Sahara.
Kosmos would continue to be the exploration operator at the deep water blocks and would retain 32.51% and 28% in the blocks off Senegal and Mauritania, respectively.
"The deal gives BP a leadership position in an emerging world-class, low-priced gas basin with advantaged access to global gas markets", the London-based company said. The total acreage, by Kosmos' estimates, could contain roughly 50tcf of gas resource potential and in excess of 1 bn barrels of liquids resource potential.
Shares of Kosmos Energy soared more than 11 percent Monday in afternoon trade after the company announced a partnership with BP to develop gas resources in Africa.
Oil major BP has struck a deal for just under $1bn (£800m) to drill for gas in Mauritania and Senegal amid the worldwide slump in oil prices. The Mauritania-Senegal basin will become an "important profit center" according to BP's upstream CEO, Bernard Looney.
British oil giant BP has signed agreed to acquire stakes in exploration blocks in Mauritania and Senegal from Kosmos Energy for $916m.
BP "brings financial capability, deep-water development and LNG expertise", said Kosmos CEO Andrew Inglis, who was formerly BP's upstream chief.