The Ethiopian government and regional forces from Tigray agreed on Wednesday to cease hostilities, a dramatic diplomatic breakthrough two years into a war that has killed thousands, displaced millions and left hundreds of thousands facing famine.
Delegates from both sides signed the agreement in the South African capital Pretoria, just over a week after formal peace talks mediated by the African Union began there.
"The two parties in the Ethiopian conflict have formally agreed to the cessation of hostilities as well as to systematic, orderly, smooth and coordinated disarmament," said Olusegun Obasanjo, head of the African Union mediation team, at a ceremony.
Obasanjo, a former Nigerian president, said the agreement also included "restoration of law and order, restoration of services, unhindered access to humanitarian supplies, protection of civilians, especially women, children and other vulnerable groups".
An agreement had not been expected so soon. Earlier on Wednesday, the African Union had invited media to what it described as a briefing by Obasanjo. It was only when the event began, about three hours behind schedule, that it became clear a truce was about to be signed.
"This moment is not the end of the peace process. Implementation of the peace agreement signed today is critical for its success," said Obasanjo, adding that this would be supervised and monitored by a high-level African Union panel.
He praised the process as an African solution to an African problem.
Ethiopian government representative Redwan Hussien, who is Prime Minister Abiy Ahmed's National Security Adviser, said all parties should be true to the letter and spirit of the agreement.
In response, Tigray delegate Getachew Reda, a spokesman for the regional authorities, spoke of the wide scale death and destruction in the region and said it was his hope and expectation that both parties would honor their commitments.
Troops from Eritrea, a separate country which borders Tigray, as well as forces from other Ethiopian regions, have taken part in the conflict on the side of the Ethiopian army.
Neither Eritrea nor the regional forces participated in the talks in South Africa and there was no mention at Wednesday's ceremony of whether they would abide by the truce.
The war stems from a catastrophic breakdown in relations between the Tigray People's Liberation Front, a guerrilla movement turned political party which dominated Ethiopia for 27 years, and Abiy, who was once part of their ruling coalition but whose appointment in 2018 ended the TPLF’s dominance.
Escalating tensions in 2018-20, including over Abiy's peace deal with the TPLF's sworn enemy Eritrea, and the TPLF's decision to defy him by holding regional elections in Tigray that he had postponed nationwide, tipped the feuding parties into war.
The United Nations says the war has led to a de facto blockade of Tigray that has lasted close to two years, with humanitarian supplies of food and medicines unable to get through most of the time.
Some aid supplies did get delivered to Tigray between March and August this year during a temporary ceasefire which broke down in August, but the World Health Organization said last week Tigray had run out of vaccines, antibiotics and insulin.
It said health facilities were resorting to using saline solutions and rags to treat and dress wounds.
The government has consistently denied blocking aid and has said it was distributing food and restoring electricity and other services to areas under its control.
Human rights violations by all sides in the war, including extra-judicial killings, raping, looting and displacing people by force, have been documented by UN bodies, Ethiopia's state-appointed human rights commission, independent aid groups and media including Reuters.
All sides have denied the allegations.