The biggest Muslim rebel group in the Philippines signed an historic pact on Thursday to end one of Asia's longest and deadliest conflicts, promising to give up their arms for an autonomous homeland.
Following four decades of fighting that has claimed tens of thousands of lives, the Moro Islamic Liberation Front (MILF) signed the peace deal with President Benigno Aquino's government at a high-profile ceremony in Manila.
"The comprehensive agreement on Bangsamoro is the crowning glory of our struggle," MILF chairman Murad Ebrahim said at the signing ceremony, using a local term that refers to a Muslim homeland.
The pact makes the MILF and the government partners in a plan to create a southern autonomous region for the Philippines' Muslim minority, with locally elected leaders by mid-2016.
"What is being presented before us now is a path that can lead to a permanent change in Muslim Mindanao," Aquino said at the ceremony, attended by more than 1,000 people.
The Bangsamoro region would cover about 10 per cent of territory in the mainly Catholic Philippines. The planned region has a majority of Muslims, but there are clusters of Catholic-dominated communities.
Muslim rebels have been battling since the 1970s for independence or autonomy in the southern islands, which they regard as their ancestral homeland dating back to when Arabic traders arrived there in the 13th century.
The conflict has condemned millions of people across large parts of the resource-rich Mindanao region to brutal poverty, plagued by Muslim and Christian warlords as well as outbreaks of fighting that has led to mass displacements. The conflict and poverty have also been fertile conditions for Islamic extremism.
The MILF, which the military estimates has 10,000 fighters, is easily the biggest Muslim rebel group in Mindanao, and the settlement was greeted with relief and optimism in the south.
The autonomous region would have its own police force, a regional parliament and power to levy taxes, while revenue from the region's vast deposits of natural resources would be split with the national government.
It would have a secular government, rather than being an Islamic state. The national government would retain control over defence, foreign policy, currency and citizenship.
But there are no guarantees the peace deal will be implemented by the middle of 2016, a crucial deadline as that is when Aquino is required by the constitution to end his six-year term.
Aquino needs to convince Congress to pass a "basic law" to create the Bangsamoro autonomous region, ideally by the end of this year to allow time for other steps such as a local plebiscite.
Powerful Christian politicians in Mindanao are regarded as potential deal breakers, while others elsewhere may see political advantage in opposing the deal to appeal to some Catholics ahead of the 2016 national elections.
Islamic militants opposed to the peace deal are another threat, and could continue to create enduring violence in Mindanao.