By Helen Murphy
BOGOTA (Reuters) - Colombia's President Juan Manuel Santos has taken another apparent potshot at his predecessor, comparing him with tyrannical Roman Emperor Caligula in an increasingly heated internal dispute over the direction of peace talks with Marxist rebels.
In what Colombians saw as another veiled poke at former leader Alvaro Uribe, who has publicly criticized peace talks with FARC rebels, Santos, 61, said some past presidents had wanted war for its own sake.
"Yes, there are some leaders, some heads of state in the past, in history - Caligula liked to make war just because, because he lived for war," the president said in comments carried on his website late on Thursday.
"But that's not logical, it makes no sense. One has to look for peace. It's a constitutional mandate, but we don't need mandates to seek peace. It's an obligation."
The mandate reference appeared to be pointed at former President Andres Pastrana, 58, who led a drive for peace in 1999 that ended in shambles three years later.
Pastrana has said he was the only president with a real "mandate" to seek peace, and has also been critical of Santos.
Santos, the scion of one of Colombia's most powerful families, and the two former presidents have been sparring for several months over how to end the half-century-old conflict.
Uribe, 60, whose father was killed in a botched kidnapping attempt by the Revolutionary Armed Forces of Colombia, or FARC, is furious at what he sees as a deterioration in security under Santos and the government's bowing to FARC demands at the negotiating table in Cuba.
Santos' Caligula comment was assumed by local media to have been an erudite dig at Uribe.
Emperor of Rome between 37 and 41 AD, Caligula was "a mad and unpredictable tyrant," according to the Encyclopaedia Britannica. He was murdered along with his wife and daughter.
Uribe, de facto leader of the opposition, is angered at the possibility Santos would allow FARC leaders to sign a peace accord and not serve jail time for crimes stretching back decades.
Santos has said that such discussions have not yet taken place during peace talks between the rebels and Colombia.
The talks are a big political risk for Santos, who took office after serving as Uribe's defense minister, and may seek re-election in 2014.
Negotiations in Cuba have stretched almost seven months and the two sides have been unable to agree on the first of a five-point agenda. But Santos, a keen poker-player, is optimistic.
"Let's make this reflection," Santos said. "If we achieve an end to the conflict, if we reach an accord in Havana, who hands in their weapons, and who keeps them? And therefore, who won?"
(Reporting by Helen Murphy; Editing by Andrew Cawthorne and Philip Barbara)