Colombia’s largest rebel group, the Farc, has postponed the release of three hostages, reportedly blaming the move on the media presence in the area.
President Juan Manuel Santos called it an “unacceptable excuse” and demanded the prompt release of the men.
The left-wing rebels had said two policemen would be released on Thursday and a soldier, on Saturday.
Despite ongoing peace talks, tensions have been rising since the Farc ended a unilateral ceasefire last month.
On Wednesday, at least seven Colombian soldiers were killed and another five injured in clashes with the left-wing rebels.
The Farc were planning to release two policemen and a soldier in the region of Cauca.
But the heavy media presence led to their calling off the operation, a representative of the International Committee of the Red Cross told journalists.
President Santos reacted angrily to the move.
“Nobody understands that because of the presence of a few media, which is something that is not under the control of the government, they continue to deprive those policemen of their freedom,” he said.
The rebels did not announce a new date for the release of hostages said the organisation, said the Red Cross, which was heading the operation to pick up the hostages.
The Farc and the government have been holding peace talks in Cuba to try to end their almost five-decade-old conflict.
But on Wednesday, at least seven Colombian soldiers were killed and another five injured in clashes with the Farc in Caqueta in another escalation of the violence since the end of the unilateral cease fire.
The Colombian government saying it will only end its operations against the Farc once a peace agreement has been signed.