Talks to end Colombia's five-decade conflict have entered what the government called a "decisive phase" as army officers and FARC rebels began work on the terms of an eventual ceasefire.
The creation of the "subcommission" to propose the framework for an eventual ceasefire and disarmament marks the first time active combatants from both sides have come together around the same table during the nearly two-year-old peace negotiations.
"We've entered a decisive moment in the process. There's a real possibility of ending the conflict," said the government's chief negotiator, Humberto de la Calle.
The panel's launch came on the heels of two other key developments at the talks in Havana, the launch of a "historical commission" tasked with tracing the origins and impact of the conflict, and the start of testimony from victims, intended to help reach a deal on reparations.
"This week, we have put in march three enormously important mechanisms that are going to strengthen and guide the (government and rebel) delegations' work in this decisive phase," de la Calle said.
"In the past few days, the process has taken on a new dynamic... We are in an advanced phase of the conversations."
He said the new subcommission, headed on the government's side by the army's top general, Javier Florez, would not negotiate the actual ceasefire but rather "prepare possible future mechanisms" for a ceasefire to pass on to the two delegations.
The FARC's chief negotiator, Ivan Marquez, for his part said the creation of the subcommission meant that for the first time "active members of both sides' armed forces... are sitting down as equals to begin discussions."
But a FARC member speaking on condition of anonymity said the rebel group, which has not publicly named its representatives on the panel, was frustrated because "the government can bring the people it wants and we can't."
Since the FARC (Revolutionary Armed Forces of Colombia) was founded in the 1960s, the Colombian conflict has killed 220,000 people and caused more than five million to flee their homes.
Talks to end the conflict have so far produced deals on three points: land reform, political participation for the rebels and curbing the drug trafficking that has fueled the fighting.
The unsettled issues are reparations, disarmament and the mechanism by which the final peace agreement will be adopted.