Sudan's shaky peace process enters a critical phase on Monday when talks resume with experts warning that failure could spark even greater destruction in a conflict that has already killed two million people.
The warring factions in Africa's biggest country have been trying to negotiate an end to their 20-year-old conflict for the past year, and observers say they have reached a crunch point.
"If this best chance for peace in 20 years is missed, the arms build-up on both sides suggests the war will become more deadly and destructive than ever," said the International Crisis Group think tank.
"Any crack in the international community's unanimity (in supporting talks) would allow the parties to back away from an attainable peace and condemn Sudan to further war and famine."
The Sudan government and southern rebel Sudan People's Liberation Army (SPLA) have been fighting over religious freedom, oil, ideology and the right of southerners to rule themselves.
Delegates were heading on Sunday to a hotel in central Kenya where the talks are to be held. The first session of negotiations was expected to start on Monday, delegates said.
Mediators working for a regional conflict resolution body called IGAD have said they are aiming for a final peace deal this month and the combatants are under pressure to compromise.
Washington warned both sides in July that the international community would lose interest if a deal was not struck soon.
Peace efforts were dealt a blow last month when the government attacked regional mediators' proposals to give the north and south separate armies and central banks, and for Islamic law not to apply in the capital, Khartoum.