Cheers rang out as one by one, representatives from the transitional government and rebel groups signed the deal, a year after the peace talks began, at a ceremony in the South Sudanese capital Juba.

The deal covers a number of tricky issues, from land ownership, reparations and compensation to wealth and power sharing and the return of refugees and internally displaced people.

Ending Sudan's internal conflicts has been a top priority of the transitional government, in power since longtime dictator Omar al-Bashir was ousted in a pro-democracy uprising.

"For us today it is a historic day... this will stop the war... we are very committed to the implementation of all the protocols agreed upon," said the head of Sudan's transitional sovereign council General Abdel Fattah al-Burhan.

"This agreement will help Sudan to transform smoothly to a state of justice, citizenship, freedom and democracy."

Both al-Burhan and Prime Minister Abdalla Hamdok, as well as the European Union and United Nations, called on two powerful holdout rebel groups to join the peace process.

"We are waiting for you to achieve a comprehensive peace in Sudan," said Hamdok, who said the deal would not only silence the guns but also "stabilise the economy".

- 'Important milestone' -

United Nations Secretary General Antonio Guterres hailed the deal as a "milestone on the road to achieve sustainable peace" in a recorded video message.

"Now it is critical that this agreement translates into tangible improvements in peoples' lives."

EU foreign policy chief Josep Borrell said the deal "signifies an important milestone for the ongoing democratic and economic transition of Sudan".

The agreement was signed by the Sudan Revolutionary Front (SRF), which comprises rebel groups from the war-ravaged western Darfur region, as well as the southern states of Blue Nile and South Kordofan.

Guarantors of the deal from Chad, Qatar, Egypt, the African Union, European Union and United Nations also put their names to the agreement.

One of the rebel groups which did not sign is the Darfur-based Sudan Liberation Movement (SLM) faction led by Abdelwahid Nour, which launched an attack on Monday, the army said.

Another, the South Kordofan-based wing of the Sudan People's Liberation Movement-North (SPLM-N) led by Abdelaziz al-Hilu, has signed a separate ceasefire.

It allows rebels to keep their guns for "self-protection" until Sudan's constitution is changed to guarantee the separation of state and religion.

South Kordofan and to a lesser extent Blue Nile state have significant Christian populations who have fought for decades to end the imposition of Islamic law by Khartoum.

- 'Economic realities' -

The peace talks were mediated by South Sudan, whose leaders themselves battled Khartoum as rebels for decades before achieving independence in 2011 and who are still struggling to bring peace to their own country.

South Sudan President Salva Kiir warned that implementing the deal would not be an easy task and urged the international community to lend its support.

"We have no illusion that the implementation of the peace agreement we are celebrating today will be an easy business especially with the economic realities facing Sudan presently," he said.

"Sudan needs financial resources to rebuild the infrastructure destroyed by the war and floods."

The economy has suffered from the country's inclusion on Washington's terror blacklist, decades-long US sanctions and the 2011 secession of the country's oil-rich south which deprived the north of three-quarters of its oil reserves.

Economic hardship triggered the anti-Bashir protests and remain a pressing concern -- food prices have tripled in the past year and the Sudanese pound has depreciated dramatically.

Recent flooding, which has affected nearly 830,000 people, has worsened the situation.

The Arab-dominated government that was led by Bashir for three decades fought multiple conflicts with non-Arab rebels, including a devastating war in Darfur and the 1983-2005 war that led to the secession of the south.

The final signing ceremony was held at the Mausoleum of John Garang, one of the south's leaders during the war for independence.

Entertainers from South Sudan and Sudan performed for thousands of guests, many of them Sudanese refugees.

Abdal Aziz, 32, who fled Darfur six years ago and has been living as a refugee in South Sudan, said he believed the peace deal would end the conflict.

"It is well known since independence of Sudan there is no stability, there is no social economic development," he said.