South Sudan on Monday issued exploration and production rights in its hitherto dormant Block B3 oil field to Nigeria-based Oranto Petroleum Limited.

The oil field that straddles across northern region of Jonglei, Lakes and Central Equatoria will cost about 3 billion U.S. dollars within four years of exploration leading to drilling.

"What we have just signed is an Exploration Production Sharing Agreement (EPSA) for Block B3. This Block (B3) is awarded today to Oranto Petroleum Limited," The minister of petroleum Ezekiel Gatkuoth told journalists in Juba.

"They (Oranto) will immediately start exploring this Block. They are sharing this Block with our Nile Petroleum Corporation (Nilpet) and the distribution of the shares of this Block, 90 percent will go to Oranto and 10 percent to Nilpet," he revealed.

War-torn South Sudan is reeling from hyper inflation nearing 800 percent, following more than three years of violent conflict that reduced oil production capacity in northern oil fields located in Unity and Upper Nile regions.

Oil production declined from over 350,000 barrels per day (bpd) to less than 130,000 bpd due to fighting destroying oil infrastructure, and the situation was further exacerbated by the low global oil prices, hence battering South Sudan's nascent economy which depends 98 percent on crude oil export to finance its fiscal budget.

"We believe that the petroleum resources in block B3 are vast; to reach our target in this Block we must move quickly to explore and double our current oil production," Gatkuoth disclosed.

"The government is working hard to make sure the petroleum industry is explored so that we can have more revenues," he said.

Meanwhile, Oranto petroleum limited Chief Executive Officer Prince Arthur Eze, downplayed probable risks surrounding the EPSA reached with the South Sudanese government, vowing to fast track the unexploited oil well despite security risks involved.

"The contract says first phase two years, and then second phase two years. We start now to better the data, process, interpret it and plan for our way to drill (oil). We are in hurry the country is changing and we want to change with the country," he said.

South Sudan descended into violence in December 2013, following political dispute between President Salva Kiir and his former deputy Riek Machar. The war has killed tens of thousands, displaced more than two million from their homes.

Renewed violence in July 2016 threatened to tear apart a fragile 2015 peace agreement to end the conflict, and the UN in late February declared famine in some parts of the country leaving 100,000 people starving and 5.5 million in urgent need of humanitarian food assistance.