"The Sudanese government must prevent this crisis does not deteriorate in a way to stop the shooting, including bombings, the expulsion of citizens and intimidation," added Obama.
Meanwhile, hundreds of thousands of people forced to leave their homeland due to violence that took place just weeks before the independence of the South already.
The violence near the border of North and South Sudan is considered the United Nations (UN) also endanger humanitarian missions. Armed militia roadblocks built blocking various aid reaches thousands of refugees who need them.
The UN refugee agency said it asked the government of Khartoum to allow planes to land at major airports Kadugli, South Kordofan. North Sudan troops accused of targeting the targets where the pro-Southern Sudan.
Already last month armed conflict broke out in North and South along the border near the disputed town of Abyei. The dispute was sparked fears of civil war that had stopped in 2005 will again be repeated.
Earlier this week, Sudan and South Sudan agreed to withdraw their military from the Abyei region and hand over security to the army of Ethiopia.
