HAVANA - The Revolutionary Armed Forces of Colombia (FARC) rebels renewed their call for a ceasefire Tuesday amid peace talks with the government.

"We would really like to achieve a bilateral ceasefire," Ivan Marquez, chief negotiator and No. 2 leader in the FARC, told reporters before the new round of talks began at the Havana Convention Center. "We could begin these talks in a much more positive atmosphere."

The two sides should "at least try to reach an accord to 'regulate' the war, and to ease the impacts and effects of the confrontation on the civilian population in particular, as well as on the combatants on both sides," he added.

Marquez explained that regulation meant "establishing rules as a practical measure to force the warring sides to behave according to civilized criteria."

The peace talks started in November 2012 to negotiate an end to the five-decade fighting between the leftist rebels and the Colombian troops. Bogota has rejected a rebel-proposed ceasefire, saying it wanted to maintain military pressure on the rebels to facilitate negotiations.

The Colombian government also said earlier that attempts to cease fire during peace talks have allowed the rebels to launch new offensives.

The FARC, founded in the early 1960s by poor landless farmers, is fighting for better conditions in rural Colombia.

Six key issues will be discussed at the latest talks, including agrarian reform and the rebels' political participation, drug trafficking, reparations for the victims, disarmament of the rebels, and the implementation of a peace deal.