UNITED NATIONS - The UN Security Council demanded on Thursday that the Sudanese Armed Forces (SAF) of Sudan and the Sudanese People's Liberation Army (SPLA) of South Sudan cease fighting and resolve issues causing contention between them.

"The Security Council demands a complete, immediate and unconditional end to all fighting; withdrawal of the SPLA from Heglig; end to SAF aerial bombardments; end to repeated incidents of cross-border violence between Sudan and South Sudan; and an end to support by both sides to proxies in the other country," said the council in a presidential statement.

The statement, which had the backing of all 15 council members, was read in an open door council meeting by Susan Rice, the Permanent Representative of the US to the UN, who also serves as council president for the month of April.

The council expressed its "deep and growing alarm" at the escalating conflict that it said was most recently manifested by the SPLA seizure of the town of Heglig and its oil fields, located in the South Kordofan State of Sudan.

"The recent violence threatens to return both countries to full scale war and the period of tragic loss of life and suffering, destroyed infrastructure, and economic devastation, which they have worked so hard and long to overcome," said the presidential statement.

The council called in the statement for a safe demilitarized border zone to be established between the two countries, as well as the activation of the Joint Border Verification and Monitoring Mechanism.

The council also urged Sudan and South Sudan to resolve their differences, including those left over from the Comprehensive Peace Agreement (CPA) that ended the long civil war between north and south in 2005.

"The Security Council calls upon the governments of Sudan and South Sudan urgently and peacefully to resolve the fundamental issues of security and border management, the situations in Southern Kordofan and Blue Nile, and Abyei and all outstanding CPA issues that are fueling the mistrust between the two countries," said the statement.

"It further calls on the leaders of Sudan and South Sudan to meet immediately in a summit as previously planned in order to advance the issues that stand in the way of achieving lasting peace," it added.