Nigeria’s state oil company said on June 29 it had agreed to a joint venture to cover the more than $700 million cost of developing new oil fields in its southern Niger Delta energy hub.

The Nigerian National Petroleum Corp. (NNPC) said it had a tripartite agreement with local energy firm First Exploration and Petroleum Development Co. and international oil services company Schlumberger Ltd. (NYSE: SLB) to develop the Anyala and Madu fields under oil mining licenses (OML) 83 and 85.

The OPEC-member state has been seeking investment to increase its crude oil reserves to 40 billion barrels (Bbbl) by the year 2020, up from the current proven reserves of 37.2 Bbbl.

NNPC, in an emailed statement, said under the agreement Schlumberger would provide the $700 million investment in developing the fields, which would add 193 million barrels of crude to current reserves.

The state oil company said it would also add 800 billion cubic feet of gas to Nigeria’s proven gas reserves. Nigeria has the world’s ninth largest gas reserves, at 187 trillion cubic feet.

“In terms of daily production, the fields will yield 50,000 barrels of crude oil per day and 120 million standard cubic feet of gas per day by early 2019,” NNPC spokesman Ndu Ughamadu said in the statement.

The state oil company said OMLs 83 and 85 were located in shallow waters 40 km (25 miles) offshore.

NNPC said it held a 60% interest in the licenses, while First Exploration and Petroleum Development Co., operator of the joint venture, held the remaining 40%.