2. Sudan and Southern Sudan The length of the border is 1,350 miles. The war between Sudan and South Sudan had been going on since 1955 till 2005 over oil reserves in South Sudan's Unity state and Sudan's South Kordofan. Nearly, 2.5 million people had been killed and 5 million displaced.
In January, 2005 a peace deal was signed which provides permanent ceasefire, autonomy for the South , a power sharing agreement involving rebels in Khartoum and a south Sudanese referendum on independence in six years' time.