The government's going back and forth on a ceasefire in the south has interrupted food supplies to refugees and put some half million southern civilians at risk of starvation. The government continues to seek the expulsion of pro-rebel civilians from areas containing oil fields. This has become the major point of contention between the rebels and the government. The oil fields are in the south, but the northerners are keeping all the oil revenue for themselves and using that money to pay for troops to keep the southern oil fields by force. The rebels want a referendum in the south so the people can decide who will rule them, and who gets the oil money.