A delegation from the National Liberation Army (ELN) flew on Sunday to Cuba's capital Havana from the Colombian city of Medellin for peace talks with the Colombian government, reports said.
The rebel group will hold talks on Oct.16-19 with civil society groups, in preparation for the fourth round of peace talks with the Colombian government slated for Oct. 20-25.
The first round of talks began in December 2005, and all three previous rounds were supported by observers from Norway, Spain, France and Switzerland.
The 4,500-strong ELN has indicated willingness to reach a deal with the government, pledging to negotiate sincerely.
While a general amnesty for the ELN was a key demand, the guerilla group's leader Antonio Garcia said earlier that the government's insistence on only disarmament and not on tackling poverty was holding back the talks.
"We have to understand that the armed conflict is not merely a public order and legal problem, but part of a political, economic and social crisis, which must be overcome in order to build a real peace," he said.
The ELN is Colombia's second largest rebel group. The largest, the Revolutionary Armed Forces of Colombia (FARC), is engaged in separate talks to free hostages in exchange for jailed FARC guerillas.