Colombia's main rebel group announced Thursday it will no longer recruit guerrillas younger than 17 years old, addressing a practice widely condemned by human rights groups.

Rebel spokesman Ivan Marquez made the statement in Havana at the end of another round of peace talks between the Revolutionary Armed Forces of Colombia and the government.

Marquez said that until now, the rebels have recruited children as young as 15. He also accused the government of systematically training minors to infiltrate rebel ranks.

President Juan Manuel Santos welcomed the move as a step in the right direction after calling on the FARC to demonstrate its commitment to the 2-year-old peace process by winding down its attacks even before a final deal is reached. But he said the age limit should be higher and he also questioned why the FARC won't release minors already within its ranks.

It's unclear how many children from mostly poor farming families have been forcibly recruited by armed groups during Colombia's half-century conflict. But the Defense Ministry says that more than 4,000 minors have left the rebel ranks in the past 14 years.

Colombia's peace talks kicked off in Norway in October 2012; subsequent talks have been held in the Cuban capital of Havana.

As of now, the two sides have reached partial agreements on three of their six items on the peace agenda: agrarian reform, drug trafficking, and political participation for former rebels.