NAIROBI, Jan. 7 (Xinhua) -- Ten aid agencies warned on Thursday a deadly conflict could return to southern Sudan unless there is urgent international action to save the peace agreement that ended one of Africa's longest and deadliest wars.

In a new report "Rescuing the Peace in Southern Sudan" released in Nairobi on the eve of the fifth anniversary of the signing of the peace agreement between the Sudanese government and the Sudan People's Liberation Movement (SPLM), the agencies said a lethal cocktail of rising violence, chronic poverty and political tensions has left the peace deal on the brink of collapse.

"It is not yet too late to avert disaster, but the next 12 months are a crossroads for Africa's largest country," said co-author of the report Maya Mailer, policy advisor for Oxfam.

"Last year saw a surge in violence in southern Sudan. This could escalate even further and become one of the biggest emergencies in Africa in 2010."

The agencies also warned that growing frustration over the lack of development in southern Sudan is harming the chances of peace.

Less than half the population has access to clean water and maternal mortality rates are among the worst in the world.

There are fewer than 50 km of tarmac road in the entire region, an area the size of France, and during heavy rains many areas are cut off for months at a time, making the delivery of humanitarian aid almost impossible.

Some 80 percent of adults cannot read or write and one in seven children die before their fifth birthday.

"After five years of peace, southern Sudan remains one of the poorest regions on earth. People hoped the peace would bring economic benefits and development, but this has happened far too slowly and in some areas not at all," Francisco Roque, country director of Save the Children in South Sudan.

"We are very worried about children who seem to be increasingly targeted in attacks on villages. International donors and the government must urgently improve aid to these areas."

According to the agencies, some 2,500 people were killed and 350,000 fled their homes last year, a human toll greater than in Darfur last year.

The aid agencies -- Christian Aid, Cordaid, Handicap International, ICCO, International Rescue Committee, Oxfam International, Save the Children Sudan, Caritas France/ Secours Catholique, TearFund and World Vision -- said the rest of the world has largely overlooked this suffering.

Communities say that women and children have increasingly been targeted in attacks on villages and the government of southern Sudan and international peacekeepers have not been able to protect them.

The report says the next 12 months will see a number of potential flashpoints that could inflame violence if not properly prepared for.

These include Sudan's first multi-party elections in 24 years and a referendum in which southerners will vote on whether to remain united with the north or to secede and become independent.

To safeguard civilians at this fragile juncture, the agencies urged the UN Security Council to ensure that protecting civilians becomes a core priority for the UN peacekeeping force, UNMIS.

The agencies also called on the international community to help mediate between the northern and southern parties before the elections and referendum, to reduce the likelihood of conflict, and to support the government in the south to provide security.

International Director of Christian Aid Paul Valentin warned that a return to conflict would have devastating consequences that extend far beyond southern Sudan, the agencies said.

"Sustained diplomatic engagement from the international community, including Sudan's neighbors, is what is needed. This helped achieve what many thought was impossible and secure the peace agreement in the first place," Valentin said.

"Now engagement is needed again to ensure all that effort does not go to waste. A return to war is by no means inevitable, but it depends whether the world heeds the warning signs of the past year and has the political will to save the peace," he said.

The civil war was responsible for the deaths of two million people and forced around four million people to flee their homes, most into neighboring countries.

The war destabilized the entire region, fuelling conflicts and suffering across central and eastern Africa.

The crisis in southern Sudan is escalating at a time when the situation in Darfur, in western Sudan, remains one of the world's biggest humanitarian emergencies.

The agencies warned that there cannot be sustainable peace in Darfur if the peace between north and south is allowed to fail.

The 2005 Comprehensive Peace Agreement was signed on Jan. 9, 2005, ending a war between northern and southern Sudan that cost two million lives.