By Karen Allen
BBC East Africa correspondent
Sudan is being accused of continuing to give sanctuary to members of Uganda's rebel Lord's Resistance Army.
The Lord's Resistance Army is known for its brutality
The group has killed tens of thousands of people in the past two decades.
Recently however, there has been a fresh spirit of co-operation between Uganda and Sudan's new government of national unity.
But the International Crisis Group says there are credible reports that elements of the Sudanese military are still aiding the LRA.
A report by the think-tank says that corruption, abusive behaviour and lack of equipment has stifled efforts by the Ugandan army to quash the insurgency.
The LRA, known for its brutality and use of child soldiers, has instilled fear among people in northern Uganda, forcing more than 1.5 million people to flee their homes.
Efforts to negotiate a peace deal have stalled and arrest warrants for key LRA lieutenants issued by the International Criminal Court have failed to yield results.
The International Crisis Group is critical of both regional governments and the international community for failing to deal with what they see as a neglected war, and argue that a comprehensive strategy involving both military and non-military elements must be drawn up.