The three countries, known as the Sudan Troika, called the agreement the "first step" to restore stability and hope for the Sudanese people who have suffered for years amid violent conflict.

"The peace agreement lays a foundation for sustainable peace and stability in Darfur and other conflict-affected areas that is critical for Sudan's democratic transition," the Troika said in a statement.

They said both sides had made important concessions and urged the implementation of the deal "in good faith", pointing to the need for more peace talks with other rebel groups.

They said the risks to sustainable peace remain high given ongoing violence in Darfur, Port Sudan and South Kordofan and Blue Nile states.

"The Troika urges the Sudan People's Liberation Movement-North-Abdelaziz al-Hilu and the Sudan Liberation Movement-Abdulwahid Al Nur to build on this achievement and to engage in serious negotiations with the government," they said.

"The Troika urges Sudan's diverse communities to overcome old enmities and to unite to support this singular opportunity for lasting peace."

The deal agreed Monday is seen as a crucial step towards ending 17 years of conflict in which hundreds of thousands of people were killed.

Fighting in Darfur alone left around 300,000 people dead after rebels took up arms there in 2003, according to the United Nations, with former government leaders accused of carrying out genocide and of crimes against humanity.