Sudan and South Sudan have resumed talks on oil revenue sharing and other issues that have raised bilateral tensions to the boiling point. The talks are being held in Addis Ababa under African Union mediation.
A fresh round of negotiations began late Friday at a luxury Addis Ababa hotel.
The Sudanese and South Sudanese defense ministers led the opening session. A spokesman said the two sides discussed a framework to govern how they would interact on border issues.
Diplomatic observers at Friday's talks say the preparatory nature of the opening session indicates the deep mistrust between the two sides. Both Sudan's President Omar al-Bashir and South Sudanese President Salva Kir have in recent days suggested the neighbors may be close to war.
The last round of talks two weeks ago ended in mutual recriminations, with the south cutting off the flow of the oil that is critical to the economies of both countries.
The south is likely to suffer from the cutoff more because oil generates about 97 percent of its income. But chief negotiator Pagan Amoum emerged from that round of talks saying South Sudan would rather lose all its revenue than allow their oil to be stolen.
"So you are right, South Sudan is losing and stands to lose," said Amoum. "It is because the government of Sudan is stealing and robbing the resources. That is why we are losing."
South Sudan's Oil Minister Stephen Dhieu Dau recently said he believes the Khartoum government is imposing impossible conditions and fees on the oil to punish the south for seceding from the north last July.
"What we need from them is acceptance of the best state practice, the international experience in a case like ours where by the landlocked country is allowed to transit, to pass the commodities based on a reasonable agreed fees between the two countries," said Dhieu Dau. "But unfortunately Khartoum is introducing punitive fees, discriminatory fees against South Sudan as a penalty for the secession."
With tensions running high, several international actors are working closely with the African Union mediation team, which is led by former South African president Thabo Mbeki. The United States, Britain, Norway and China all have senior envoys involved in seeking an agreement.
Amanda Hsiao of the Washington-based Enough Project says urgent action is needed to prevent a further escalation of hostilities.
"To prevent a complete collapse in North-South relations, the international community needs to seize on this next round of negotiations as their last-ditch opportunity," said Hsiao. "All efforts must be made, all diplomatic levers must be pulled to pull the two sides closer together, to reconcile their differences and to get them to sign a comprehensive agreement."
With no end to the dispute in sight, South Sudan this week signed a memorandum of understanding with Ethiopia to build an alternative pipeline to the port of Djibouti. South Sudanese Information Minister Barnaba Marial Benjamin was quoted as saying a U.S.-based company could build the line in six months.
The current round of Addis Ababa talks is expected to last at least a week. Negotiations on the most contentious issue, sharing oil revenues, are scheduled to begin next Tuesday.