The biggest Muslim rebel group in the Philippines will sign a peace deal on Thursday aimed at ending four decades of deadly conflict that has condemned millions in the nation's far south to brutal poverty. The agreement between the Moro Islamic Liberation Front (MILF) and President Benigno Aquino's government envisages a new, southern autonomous region for the Philippines' Muslim minority with locally elected leaders by mid-2016. "For many years we have been leading the Bangsamoro people's struggle and our people have gone through a lot of hardships," MILF vice chairman Ghazali Jaafar told AFP, using a local term for the Philippines' Muslim minority. "This agreement is very important to us because this ends the fighting in Mindanao." Muslim rebels have been battling since the 1970s for independence or autonomy in the southern region of Mindanao, which they regard as their ancestral homeland. The conflict has left tens of thousands of people dead while Mindanao has become one of the nation's poorest and most corrupt areas, with Muslim and Christian warlords ruling over large parts. The fighting and poverty has also proved to be fertile conditions for Islamic extremism, with the Al-Qaeda linked Abu Sayyaf group and other hardline militants making remote regions of Mindanao their strongholds. The MILF, which the military estimates has 10,000 fighters, is easily the biggest Muslim rebel group in Mindanao, and Aquino believes a political settlement is the key to securing a lasting peace. "It is important, it is historic. It is going to be a major contribution for the peace and development of the entire country," Aquino's adviser on the peace process, Teresita Deles, said this week. Aquino and MILF chairman Murad Ebrahim will oversee the signing of the peace deal during a high-profile ceremony at the presidential palace in Manila attended by about 1,000 people, including Malaysian Prime Minister Najib Razak. Malaysia has hosted and brokered the peace talks, which began 17 years ago. The peace deal outlines plans to create a Bangsamoro self-rule area in Mindanao that would cover about 10 percent of territory in the majority Roman Catholic-populated Philippines. The autonomous region would have its own police force, a regional parliament and power to levy taxes, while revenues from the region's vast deposits of natural resources would be split with the national government. The national government would retain control over defence, foreign policy, currency and citizenship. Fragile peace However 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. But even though Aquino's ruling coalition has a loose majority and he still enjoys record-high popularity ratings, there are concerns politicians could reject or water down the proposed law 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. "There is a danger that this could be hijacked by politically savvy and entrenched politicians," Jesus Dureza, the chief peace negotiator with the MILF from 2001 to 2003, told AFP. Islamic militants opposed to the peace deal are another threat, and could continue to create enduring violence in Mindanao. Among the potential spoilers is the Bangsamoro Islamic Freedom Fighters, an MILF splinter group of a few hundred militants that has carried out deadly attacks in the south in recent years. Troops have been placed on high alert in the south, in case militants seek to distract from Thursday's peace deal with attacks. The MILF leadership has committed to working with the government to neutralise the threat of the BIFF. However the MILF will not give up its arms or the identities of its fighters until the basic law has been passed, highlighting the fragility of Thursday's peace deal.