Chavez denies supporting Farc, saying his contacts with the group are aimed at securing the release of its hostages.
Farc holds hundreds of captured security personnel as well as dozens of hostages who it hopes to swap for its own imprisoned fighters.
Plea to Cano
Chavez specifically called on the new Farc leader to release all prisoners held by the group in jungle camps.
Farc confirmed last month that Manuel Marulanda, their longtime leader and founder, had died and been succeeded by Alfonso Cano.
"The time has come for the Farc to release everyone ... It would be a grand humanitarian gesture and unconditional," Chavez said.
"This is my message for you, Cano: 'Come on, let all these people go.' There are old folk, women, sick people, soldiers who have been prisoners in the mountain for ten years."
Western countries such as France have pushed for regional diplomacy to free dozens of hostages, who include Ingrid Betancourt, the French-Colombian politician.
Colombian officials say Farc is at its weakest point in years due to the deaths of several senior members as well as high-profile defections and battlefield losses.
Chavez's appeal to Farc came a day after he revoked a law decreed last month creating four spy agencies and a Cuban-style national informants' network.
It had sparked outrage among opposition members and human rights groups.
The law, which the government said was needed to block US interference in Venezuelan affairs, made it a crime to refuse to co-operate with intelligence agencies and to publish information deemed "secret or confidential".