Chavez said the FARC has "become an excuse for the (US) empire to threaten all of us ... the day that peace arrives in Colombia, the empire will have no excuse."

Washington has labeled the FARC a terrorist group and joined the Colombian government in accusing Chavez of aiding the group. Chavez has rejected the charges, saying he only had contacts with its leaders for discussion on the prisoner release, a job Chavez has been engaged in for months.

The FARC has yet to respond to Chavez's latest call.

Policy shift at special time 

Chavez's comments, in which he publicly addressed the new FARC leader for the first time, appears to mark a shift of his government's policy toward the group just months after he called for the FARC to be recognized as a legitimate insurgent force.

His call came at a time when the FARC is said to be at its weakest point, or at what some analysts say is a turning point, in years in its decades-long anti-government fight, due to senior leaders' deaths, high-profile defections and battlefield losses.

Under Colombian President Alvaro Uribe's military onslaught, FARC forces have been almost halved to 8,000, according to government estimates.

The group acknowledged last month that its top leader and co-founder Manuel "Sureshot" Marulanda had died of a heart attack.

Its second-in-command Raul Reyes was killed by the Colombian army in a March cross-border attack on a rebel camp.