Colombia Reports said the New Year's Eve message was posted on YouTube but then removed as government forces said at least five FARC guerrillas were killed in a military offensive in southwestern Colombia.
"We expect 2013 to be a year of political, economic and social gains, through struggle and mobilization," chief negotiator "Ivan Marquez" said.
The video was shot in Cuba, where FARC -- the Revolutionary Armed Forces of Colombia -- and government representatives have been negotiating an end to the half-century-old conflict, Colombia Reports said. The negotiations have been suspended since Christmas.
Meanwhile, government forces and rebels battled for 12 hours on the border of Cauca and Huila departments. In addition to the five dead, 11 rebels were injured.