"Faced with the war with which (the authorities) responded to our desire for peace for COP16, we invite delegates from the national and international community to refrain from attending this event," the Central General Staff (EMC) group said in a post on social media platform X.

Around 12,000 people, including representatives from some 200 countries, are expected to be at the UN-led conference. Colombia's President Gustavo Petro said Saturday that "the security of COP16 is guaranteed."

The EMC's message comes in the wake of a military raid that wounded around 17 people in the village of El Plateado in the Cauca department, where the armed group is active.

A dissident faction of the disbanded FARC guerilla group, the EMC has already threatened the summit, saying in July that it "will fail even if they militarize the city with gringos (Americans)."

Colombian army vehicles and troops have been patrolling the streets of Cali -- the closest city to EMC-dominated territory -- in a bid to bolster security for COP16, which runs until November 1.

Some 3,500 EMC members are estimated to be active and are involved in the drug trade and illegal mining, as well as fighting both the military and groups competing for trafficking routes and territory.

COP16, which takes place weeks before the COP29 climate summit in Azerbaijan's capital Baku, will assess whether rich countries are making good on their promises to stump up $30 billion a year to help the developing world save its ecosystems.