Disagreements over how Sudan and South Sudan share oil revenues have been a trigger for recent war games and deadly fighting between the two north African countries.

Both Sudans depend on oil so deeply that neither can pay their bills without it, including their debts to China.

China, as the biggest investor in both the countries, can use its enormous political clout to convince politicians in both Khartoum and Juba to come to the negotiating table.

Al Jazeera's Peter Greste reports from Juba.