The Estado Mayor Central (EMC), led by Ivan Mordisco, Colombia's most wanted guerrilla commander, rejected the 2016 peace agreement between the FARC and the government.

It is one of the main drivers of insecurity in the country, which is experiencing its worst wave of violence in a decade, as it prepares to elect a successor to leftist President Gustavo Petro.

Colombians will go to the polls on June 21 to choose a president between Senator Ivan Cepeda, a Petro ally, and far-right candidate Abelardo de la Espriella.

In a statement, the EMC announced "the extension of the suspension of offensive military actions and operations against the public security forces" from June 10 through June 23.

"We will continue to reserve the right to legitimate self-defense against attacks by Colombian or US security forces and other armed groups," the EMC secretariat said.

"We once again hope that this decision will create favorable and peaceful conditions for communities, enabling them to turn out to vote in large numbers," it added.

Petro has unsuccessfully attempted to negotiate with Mordisco as part of his "Total Peace" policy, which sought to secure the disarmament of all armed organizations in Colombia.

In April, fighters under Mordisco's command killed 21 people in a bombing attack on a highway in the southwest of the country, the deadliest attack against civilians in two decades.