A six-month ceasefire between the Colombian government and the country’s largest remaining armed rebel group, reached in the Cuban capital, Havana, on June 10, has entered into force, in the largest victory for President Gustavo Petro in his push to end decades of armed conflict.

The breakthrough is the most solid progress made by the government of Colombia's first left-wing leader, Gustavo Petro, on the path toward an end to the country's 60-year-long conflict with the armed group.

The ceasefire will last until February if not broken, having been the result of peace talks that restarted last year in a bid to rid the country of the conflict that has so far claimed the lives of at least 450,000 people.

"The ELN central command orders all units to suspend offensive operations against the armed forces, police, and security organizations of the Colombian state," ELN commander Eliecer Herlinto Chamorro - also known as Antonio Garcia - said Monday.

Garcia underlined that the ELN, a Marxist-Leninist guerrilla group that has been involved in the liberation of Colombia from US imperialism since 1964, would continue to defend itself during the ceasefire if needed.

Moreover, the government's high peace commissioner, Danilo Rueda, on Tuesday said the ceasefire would prevent violence and human rights abuses like kidnappings.

Petro and the negotiating teams will be inaugurating a committee to guarantee civil society's presence at the talks on Thursday after the remarkable agreement gave momentum to the Petro administration.

On June 10, the Colombian government and the ELN guerrilla group agreed to a six-month ceasefire in the Cuban capital, Havana, as they worked toward a peace deal to end decades of bloody conflict.

Cuban Foreign Minister Bruno Rodriguez announced that a deal for a "bilateral, national and temporary ceasefire" was signed in the presence of Colombian President Gustavo Petro and ELN leader Antonio Garcia.

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This came after the government and the ELN announced in March that they had agreed to begin negotiating a ceasefire as the two sides wrapped up a second round of peace talks in Mexico.

An agreement dating back to March said the goal of the talks was reaching an accord based on international humanitarian law.

A truce was the desire of "the entire Colombian nation," government negotiator Otty Patino indicated, adding, "We have heard that cry, and we feel that the ELN delegation has also heard it."

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The talks took place right after the left-wing leader took office back last August after former governments failed to reach any sort of accord with the rebels.

Petro suggested a multilateral ceasefire after taking office to all armed groups operating in the country in an effort to endorse peace and end decades of internal conflict.

Petro assumed office on August 7 and was a member of the M-19 insurgency - a militant faction that participated in the internal armed conflict between 1974-1990, and his call for a ceasefire came less than three weeks later.

His conservative predecessor Ivan Duque suspended the talks following a car bomb attack on a police academy in Bogota that left 22 people dead.

The negotiators reported earlier that the Colombian government had recognized the ELN as a political organization, as well as a rebel group, distinguishing it from other armed gangs, such as drug traffickers.

Colombia's first Black Vice President, Francia Marquez, who was at the conclusion of the talks in Mexico, urged the negotiators to "stay at the table no matter what" - and that they did.

Founded in 1964 by trade unionists and students, the ELN has taken part in failed negotiations with Colombia's last five presidents.