BOGOTA (Reuters) - The commander of Colombia s Marxist ELN rebels on Friday ordered his fighters to begin a ceasefire this weekend as the group struggles through complicated peace talks with the government aimed at ending five decades of war. Nicolas Rodriguez, known by his war alias Gabino, told the National Liberation Army (ELN) guerrillas to begin their part in a bilateral ceasefire agreement with President Juan Manuel Santos  government starting on Sunday and running through     mid-January. The ELN is in talks in Ecuador to end its part in a conflict involving government troops, leftist rebels, criminal gangs and right-wing paramilitary groups. Since negotiations began in February, the ELN has continued to take hostages for ransom and stepped up bomb attacks in recent weeks on oil companies.  It wasn t easy to reach this agreement but finally we achieved it. Since talks began with Santos s government we have insisted on the urgency of this ceasefire because it stops offensive actions and brings important humanitarian relief to the Colombian population,  Rodriguez said in a video message. During the ceasefire, agreed on Sept. 4, the insurgent group has pledged to suspend hostage taking, attacks on roads and oil installations, the use of landmines and the recruitment of minors. In turn, the government agreed to improve protection for community leaders and conditions for about 450 jailed rebels.  Colombians, we must never stop seeking peace. I hope this temporary ceasefire ... can be extended and become the first step to peace with the ELN,  Santos said in a national address on Friday. The center-right president signed a peace deal with the larger Revolutionary Armed Forces of Colombia in late 2016 after negotiations in Cuba that lasted four years. Founded by radical Roman Catholic priests in 1964, the ELN has sought peace with the government before but made little progress. This would be the first ceasefire with the ELN. The ELN is considered a terrorist group by the United States and European Union. 