Columbia’s Farc left-wing rebel group announced Monday -- during peace talks in Havana, Cuba -- with the Bogota government that it will cease hostilities with the military for two months.

Farc's lead negotiator Ivan Marquez described the ceasefire as “a contribution made to strengthen the climate of understanding necessary so that the parties that are starting the dialogue achieve the purpose desired by all Colombians,” the BBC reported.

The Colombian government has not agreed to observe the unilateral ceasefire -- expected to begin at midnight and last until Jan. 20 -- and has previously stated that it would not consider a truce until after a final agreement has been reached.

Bogota is concerned that the ceasefire is a move by Farc to give it more time to regroup and gather its strength.

The government has demanded that the rebels lay down their arms, which has remained a sticking point in the negotiations that began last month in Oslo with the aim of ending over five decades of conflict between the two sides.