Exxon Mobil reported that its license was renewed for 20 years for blocks in Nigeria that could collectively produce as much as 550,000 barrels of oil per day.
Austen Oniwon, managing director at state-owned Nigeria National Petroleum Corp., was quoted by Bloomberg News as saying more signings were on the way for companies like Chevron and Royal Dutch Shell "before the end of March."
Oil exploration declined in Nigeria because producers are wary of investments without laws governing the energy sector. Legislation has been stalled in Parliament since 2009, though Abuja had said a draft petroleum law would be sent to lawmakers within six weeks.
Most of the company's contracts with oil companies have been in various stages of negotiation for more than two years, though Shell officials had said they were "optimistic" things were turning the corner, Bloomberg reports.
Nigeria has at least 37 billion barrels of crude oil reserves and is the fifth-largest exporter to U.S. markets.