The London-listed company is reportedly engaged in talks for acquisition of the contract area belonging to US company Hyperdynamics off the West African country.
Cash-strapped Hyperdynamics has been seeking to offload part of its operated 77% stake in the concession amid drilling difficulties.
It said in a statement on Monday that Tullow was in talks to acquire a 40% interest under an exclusivity agreement with subsidiary SCS that expires on November 19.
If the parties reach agrermrnt, transfer of the stake would be completed by year-end. Aberdeen-based Dana Petroleum holds the remaining 23% stake in the licence.
Houston, United States-based Hyperdynamics has been facing liquidity challenges due to high drilling costs on the initial abortive Sabu-1 wildcat sunk on the 25,000 square-kilometre licence and it was forced to ditch a planned second well due to lack of cash.
Hyperdynamics may be under time pressure after being warned in May that it could face expulsion from the New York stock exchange due to its weak share price unless its performance improved within six months.
Tullow, for its part, is keen to expand its acreage position off West Africa where it is operator of the Jubilee oilfield off Ghana.