U.S. Special Envoy for Sudan Princeton Lyman on Friday left for meetings in Sudan, South Sudan and Ethiopia over outstanding issues between the two Sudans. In Khartoum and Juba, Lyman will urge Sudanese and South Sudanese leaders to continue negotiations on outstanding post- Comprehensive Peace Agreement (CPA) issues, specifically those related to oil and transitional financial arrangements, border trade and security, and implementation of the June 20 agreement on interim arrangements for the disputed Abyei region, the State Department said. The CPA inked in 2005 ended two decades of civil war between the two sides and saw South Sudan win independence on July 9, but some thorny issues remain unresolved between them, including oil revenues and external debt sharing, border demarcation and the status of the oil-rich Abyei region. Khartoum also accused South Sudan of supporting the rebels in its Blue Nile and South Kordofan areas, which have witnessed armed clashes between the Sudanese army and fighters of the Sudan People \'s Liberation Movement from South Sudan. The U.S. envoy will press the parties for \"an immediate end\" to conflict and unfettered humanitarian access in Southern Kordofan and Blue Nile, the State Department said in a statement. In Addis Ababa, Ethiopia\'s capital, the envoy will meet Ethiopian government and African Union officials on efforts to assist the Sudanese parties in resolving their outstanding issues, as well as engaging the Sudanese government on the situation in Darfur, the department said. In their meeting in Khartoum last week, Sudanese and South Sudanese leaders reiterated their commitment to resolve the outstanding issues and not to return to war again no matter what the reasons were.