Mali's Tuareg-led rebel alliance will Thursday initial a peace accord that was drawn up with the government to bring stability to the conflict-hit west African nation, Algerian mediators and the rebels said.
The Coordination of Azawad Movements (CMA) said it would initial the document to "honour previous commitments".
"This decision also follows commitments made by the international mediation and accepted by the Malian side (government) to undertake discussions on the demands and comments by the CMA after initialling and before signing the final document," it said.
The CMA said it would not be present at the actual signing on Friday.
In diplomatic language, "initialling" a deal is an agreement in principle that there is no need for further discussion on the details. But because it stops short of signing the document, it means the deal cannot be implemented.
Abdelaziz Benali Cherif, a spokesman for Algeria's foreign ministry, had earlier confirmed the CMA would signal its commitment to the document, thrashed out over months under UN auspices, in Algiers on Thursday.
The agreement is due to be signed officially on Friday in Bamako in the presence of around a dozen heads of state and government.
Mali was upended by a coup in 2012 which opened the door for Tuareg separatists to seize the towns and cities of the vast northern desert with the help of several Islamist groups.
The country has since returned to democracy but remains deeply divided between its northern Tuareg and Arab populations and the southern sub-Saharan ethnic groups they accuse of marginalising them.
The Malian government and a coalition of armed groups known as the Platform have already initialled the peace accord.
But the CMA has said it will not accept a deal without an amendment recognising "Azawad", the name used by the Tuareg for the northern part of Mali, as a "geographic, political and juridical entity".
The CMA issued a statement early on Wednesday lamenting its failure to secure the amendments it was seeking but resolved to initial the document before the opening of "intermediate discussions between initialling and signature".
The alliance said it could "only deplore the current blockages due to the obstinacy of the Malian government in trying to impose a settlement plan that does not have the support of the people of Azawad", ruling out taking part in Friday's ceremony.
Experts have pointed to fissures within the CMA, however, and two of its five groups are likely to rubber-stamp the deal on Friday, according to the mediation source.