The peace agreement which ended years of war between north and south Sudan could unravel unless immediate steps are taken to salvage it, two key former diplomats say. "Today, five years after the historic Comprehensive Peace Agreement (CPA) was signed between North and South Sudan, there is a real threat of an all-out war returning to Sudan and still no permanent resolution to the Darfur conflict," Lt-Gen Lazarus Sumbeiwyo and John Danforth warned.