Bogota - Colombian President Juan Manuel Santos on Wednesday warned his troops to stay prepared for conflict after leftist FARC rebels decided to drop their unilateral ceasefire.
The Colombian government and FARC negotiators resumed peace talks on Monday in Havana amid heightened tensions following air strikes that killed dozens of rebels in Colombia.
"Don't let your guard down," Santos told a military ceremony in his country's north.
Also Read: Drug plane from Venezuela crashes off Colombia's coast
"Now that we are going through a storm in the peace process, with the rebels saying they will end their unilateral ceasefire ... we are going to hold strong moving forward, but meanwhile, you must not let your guard down."
About 40 guerrillas with the Revolutionary Armed Forces of Colombia have died in recent days in three military operations in Cauca, Antioquia and Choco, weeks after rebels ambushed army troops and killed 11 soldiers with the unilateral ceasefire supposedly in effect.
With the fate of the peace process on the line, its guarantor countries, Cuba and Norway on Wednesday urged the rebels and Bogota to step up talks.
"We call on the parties to continue their efforts, to keep advancing on discussion of remaining issues, including reaching a deal on a permanent bilateral ceasefire and end of hostilities," Cuban diplomat Rodolfo Benitez told reporters in Havana.
The FARC has repeatedly urged Santos to agree to a bilateral ceasefire, but the president has refused to consider a truce without a final peace deal in place.
Also Read: Colombian general loses family to 'ironic' Tunisia attack
The talks in the Cuban capital have so far achieved partial deals on several issues, including political participation for rebels and ending the drug trafficking that has fueled the conflict.
But a final deal remains elusive.
The conflict has killed more than 200 000 people since the FARC was launched in 1964 in the wake of a peasant uprising.
It has also uprooted some five million people, drawing in a web of leftist rebel groups, right-wing paramilitaries and drug traffickers in a half-century of violence.