FARC leaders Rodrigo Granda alias "El Canciller" and Jesus Santrich said "it is not admissible ... to ask us for more peace signs," the Bolivarian Press Agency (ABP) reported.
Granda and Santrich were quoted as saying "the hostages held inour camps will only be liberated" on condition of "a prisoner exchange."
The rebel leaders made the statement after the French government sent an airplane to the Colombian capital Bogota in an attempt to provide medical help to kidnapped French-Colombian citizen and former presidential candidate, Ingrid Betancourt, who is one of several hostages being held by the FARC in a precarious state of health.
"We proved many times our political willingness to find solutions to the conflict and we received insults," the rebel leaders said in reference to recent tensions with the government.
Thanks to the mediation by Venezuelan President Hugo Chavez, the FARC released six hostages in January and February.
After the Colombia army launched a military operation against the FARC in Ecuadorian territory early last month, Chavez blamed Colombia for obstructing his mediation to free more hostages.
The Colombian government said on Wednesday it wants to rebuild ties with Venezuela, but prefers to let the Catholic Church and European envoys facilitate dialogue with the FARC.