Sudanese negotiators have agreed in principle on the sharing of wealth between the north and south.
The 20-year civil war has caused untold misery
Mediators have hailed the development as a major step towards ending Africa's longest running civil war.
The government and rebels at talks in Kenya have agreed to work through Christmas to try to broker a final deal before the end of the year.
The two sides now have to turn their attention to power sharing and the future of three contested areas.
The sharing of revenue from oil has been central to the current round of talks in Naivasha.
Oil accounts for more than 43% of revenues for the Sudanese government.
But most of Sudan's oil is drawn from fields in the south, an area controlled by the rebel Sudan People's Liberation Army (SPLA).
The negotiations centred on four key issues:
A separate central bank for the south;
Currency for the south;
Division of oil resources;
Petroleum commissions so the SPLA could negotiate their own oil deals.
Over the weekend, both sides agreed to divide equally the oil revenues generated in the south.
Mediators say the SPLA will be expected to pay a two per cent levy to states where the oil is extracted.
The BBC's Christian Fraser says there was informal agreement during the last round of talks to create a new national currency for the whole country and with that issue resolved it is unlikely the SPLA will have pushed for their own central bank.
The debate is more likely to have focused on how to bridge the time gap until that new national currency is ready.
The two leaders of the government and rebel delegations have now started the final phase of the talks on power-sharing and the future of three disputed regions.
The status of three regions
The disputed regions are Abyei, Nuba mountains and the Southern Blue Nile which are claimed by both the government and the rebels.
The war in Sudan which broke out in 1983 has pitted the Christian and traditionalist south and the mainly Muslim north.
The conflict has claimed about two million lives and left an estimated four million others displaced.
Mediators especially the United States, have been putting pressure on both sides to reach a deal or a framework accord by the end of the year.