By Helen Murphy and Luis Jaime Acosta
BOGOTA (Reuters) - Colombian President Juan Manuel Santos said the time for peace with Marxist FARC rebels is now or never but the instant he determines negotiations are going nowhere or strengthening the rebels, he would abandon the talks and seek resolution to the conflict on the battlefield.
Santos told local media on Monday that talks to bring an end to five decades of conflict with the Revolutionary Armed Forces of Colombia, or FARC, are going well but should speed up.
The center-right Santos has bet his legacy on resolving the war, which has killed more than 200,000 people since the early 1960s, and bringing peace to Colombia.
Santos is in the final year of his first term in office and has hinted he will run for a second term next year. He has until November to say if he will seek re-election.
"I am still optimistic," Santos said of the talks under way in Cuba. "If I see that they have no future, that there is no will on the other side, that this is going nowhere, that same day I will dismantle the negotiating table and talks will end."
Discussions with the FARC began late last year but have been slow and Colombians are beginning to lose patience. In a recent survey in the weekly magazine Semana, some 43 percent of those polled in July said they were optimistic peace could be achieved, down from 45 percent in April.
The two sides are working through a five-point agenda and so far have only agreed partially on agrarian reform. Negotiators now are discussing the FARC's inclusion into the political system and then will move on to reparations to its victims, the drug trade and an end to the conflict.
The talks are seen as a litmus test for a possible peace process with Colombia's second biggest rebel group, the ELN, or National Liberation Army. Santos has said talks with the ELN would begin immediately if it frees all its captives, including a Canadian geologist seized six months ago.
The two rebel groups have been hit hard over the last decade as a U.S.-backed offensive stepped up attacks and intelligence gathering, pushing them deeper into inhospitable jungle and mountains.
But neither the FARC nor the ELN are beaten and still are able to launch heavy attacks on military and civilian targets as well as hit at infrastructure like the oil and mining industries, key to the nation's economic growth.
Still, Santos reckons the FARC, which began as an agrarian struggle against unfair land distribution, is tied to the peace process as its only real option.
"The guerrillas have no alternative, If they don't take the peace train now, they will miss it forever," Santos told Caracol Radio. "A peace process in several years would be very difficult because among other things the rebels are getting old."
"Leading and maintaining control of the rebels after 50 years is not easy ... This is the time, it's now or never," he added.
The ELN and the FARC, both considered terrorist groups by the United States and the European Union, have battled a dozen successive Colombian governments since they were founded in 1964.
The ELN was inspired by the Cuban revolution and established by radical Catholic priests.
(Reporting by Luis Jaime Acosta and Helen Murphy; Editing by Fernando Peinado and Bill Trott)