The government of South Sudan says it has fully shut down oil production, a move sparked by a dispute with neighboring Sudan.

South Sudan initiated the shutdown last month, accusing the north of confiscating more than $800 million worth of oil being transported through northern pipelines.

Khartoum says it took the oil because the south would not pay transit fees of more than $30 per barrel.

South Sudan government spokesman Barnaba Marial Benjamin said Wednesday that authorities discovered hundreds of previously undocumented oil wells during the shutdown process.

“The shutdown of the oil fields is complete, it has been a blessing in disguise. We discovered that certain oil fields were being undercounted. The Dar blend, they used to say there were 300 wells, and now they turn out be 600.”

He says the government suspects that oil companies conspired with Sudan to keep the oil wells secret from South Sudan authorities.

South Sudan separated from the north last July, six years after the end of a 21-year civil war.

Tension between the two Sudans has been running high, and leaders on both sides have said a return to war is possible.

The sides have not been able to agree on how to demarcate their border or how to share oil revenue. The south, at independence, took over three-fourths of the oil production from the former unified Sudan.

China, the largest buyer of Sudanese oil, has urged the two countries to settle their differences through negotiations.