FARC dissident Andrey Avendaño wants a ceasefire before talking about peace with the Colombian government from Cauca, a group stronghold.
The dissidents, who rejected the 2016 peace deal, are now in talks with President Gustavo Petro without a fixed start date.
Petro, Colombia’s first left-wing president, is trying to solve the conflict by talking with all illegal groups.
On New Year’s Eve, he announced a six-month ceasefire with major groups, including the Estado Mayor Central (EMC).
The EMC is the leader of a group of FARC dissidents who decided not to participate in the 2016 peace talks between the FARC rebels and the Colombian government.
However, the government stopped the ceasefire in May after dissidents killed four indigenous children, worsening the conflict in Cauca.
Avendaño said that talking is the only way to stop the violence but criticized the government for not meeting the people’s expectations.
He warned that the EMC, with about 3,500 fighters, is ready to fight the Colombian state.
EMC is fighting other armed groups over control of drug trafficking and illegal mining.
Rebels, drug traffickers, paramilitaries, and state agents have been fighting for over 50 years, leaving more than nine million victims.
According to the UN, Colombia is the world’s biggest cocaine producer, with 204,000 hectares of coca crops.