The Colombian government and the National Liberation Army (ELN), the country’s last recognized rebel group, said Friday they would invite the United States to join their peace process.

The talks are an initiative of President Gustavo Petro, who in August became Colombia’s first-ever left-wing leader and pledged a less belligerent approach to ending violence by armed groups, including left-wing guerrillas and drug traffickers.

The parties resumed formal talks in Venezuela on Monday for the first time since 2019.

They agreed to reach out to the United States through diplomatic channels “to ascertain their willingness to participate in the process” and to send a special envoy, according to a statement from Norway, one of the guarantors of the talks.

The statement said the talks took place in an environment of “trust and optimism”.

When asked by AFP, the US State Department did not confirm any possible US involvement in the talks.

“At this time, we continue to be in touch with the Petro administration to better understand plans to seek total peace with the ELN, FARC dissidents and other criminal organizations,” a State Department spokesman told AFP, referring to on the remaining, still armed members of the rebel group the Revolutionary Armed Forces of Colombia, who subsequently laid down their arms and formed a political party.

“The ELN remains a designated foreign terrorist organization under US law,” they added.

The parties also agreed to invite Brazil, Chile and Mexico to join Norway, Cuba and Venezuela as guarantors of the process.

According to a government statement, Mexico agreed to participate in talks during Petro’s visit with Mexican President Andres Manuel Lopez Obrador on Friday.

The two leaders spoke about their “conviction to work together for peace in the region,” the statement said.

Germany, Switzerland and Spain would also be invited as “accompanying countries”, the Norwegian statement said.

Around 30 delegates are taking part in the talks, which are expected to last three weeks.

For more than half a century, Colombia has suffered armed conflicts between the government and various groups of left-wing guerrillas, right-wing paramilitaries and drug traffickers.

The ELN began as a left-wing ideological movement in 1964 before turning to crime, focusing on kidnappings, oil industry racketeering and drug trafficking in Colombia and neighboring Venezuela.

It has around 2,500 members, around 700 more than when negotiations were last broken off. The group is primarily active in the Pacific region and along the 2,200-kilometer border with Venezuela.

Dialogue with the group began in 2016 under ex-President Juan Manuel Santos, who signed a peace deal with the larger rebel group, the Marxist Revolutionary Armed Forces of Colombia (FARC), which subsequently gave up arms and formed a political party.

But talks with the ELN were broken off by conservative ex-president Ivan Duque in 2019 after a car bomb attack on a police academy in Bogotá killed 22 people.

Petro, himself a former guerrilla fighter, approached the ELN shortly after coming to power as part of his “total peace” policy.