Negotiations between the sides had been suspended in 2019 following a rebel attack on a police academy in Bogota that killed 23 people.
The Colombian government representative, José Otty Patiño, said the latest round should produce “permanent solutions … not temporary truces.”
Pablo Beltrán, the rebels’ chief negotiator, said the talks were aimed at a “temporary, nationwide cease-fire” and that any agreement should include “an alternative anti-drug policy that is no longer based on repression and war.”
The ELN, founded in 1964 and present in about 200 Colombian townships, is based in areas where cocaine production is widespread.
Petro has said that peace talks with the ELN are a cornerstone of his plan to bring “total peace” to the nation of 50 million people, where some rural areas are still under the grip of drug gangs and rebel groups despite a 2016 peace deal with the larger Revolutionary Armed Forces of Colombia, or FARC.
The ELN has around 4,000 troops in Colombia and neighboring Venezuela, where human rights groups have reported the group runs drug trafficking routes and illegal gold mines.
The rebel group was founded by intellectuals inspired by the Cuban revolution and was often smaller than the FARC. But in recent years, the ELN has become more influential in rural pockets of Colombia that were abandoned by the FARC rebels after they made peace with the government.
The ELN leadership is concerned by Petro’s plan for “total peace” with drug cartels and rebels, saying the two groups should not be treated equally.
Petro has said his administration would not negotiate with drug traffickers, and they would have to submit to justice.
Andrés Macías, who studies armed conflicts at Colombia’s Externado University, said the ELN had political aims “at least when it was founded,” and is wary of being thrown into the same basket as powerful cartels like Colombia’s Gulf Clan.
Mexico, Norway, Venezuela, Chile and Cuba are acting as guarantor nations in the ELN peace talks.
Suarez reported from Bogota, Colombia
