The Colombian government and FARC rebels said Wednesday they have set up a joint committee to mediate disputes and oversee implementation of the historic peace deal they concluded last month.

The committee, a key actor in the peace process, has three members from the government and three from the Revolutionary Armed Forces of Colombia (FARC), the two sides said in a statement.

The ultimate say, however, will fall to the Colombian government.

After 52 years at war, the Marxist FARC guerrillas have agreed to disarm, demobilize and reinvent themselves as a political party under a wide-ranging peace accord hashed out in nearly four years of negotiations in Cuba.

President Juan Manuel Santos and FARC leader Timoleon Jimenez are due to sign the deal on September 26. It will then be put to a referendum on October 2.

If it passes, the new committee will have a central role in the ensuing transition period.

It has already started work, meeting with international experts who are tasked with setting up a working group to overhaul the electoral system, making it more independent and transparent.

The committee will have an initial mandate until 2019, with an option to extend for up to a total of 10 years.

The Colombian conflict, which has drawn in various left-wing, right-wing and criminal groups, has claimed 260,000 lives.

The government has yet to begin planned peace talks with a smaller rebel group, the National Liberation Army (ELN).