An attack on a military base in eastern Colombia killed two soldiers and injured at least 21, Colombia’s military says, as tensions escalate between Colombia’s government and one of the nation’s largest remaining rebel groups.

The decision is another devastating blow to President Gustavo Petro's cornerstone total peace policy, which looked to remove the ELN from its role in the Andean country's six-decades of internal armed conflict.

An attack with explosives by Colombian leftist rebel group the National Liberation Army (ELN), which left more than two dozen troops injured and two dead, has "practically" ended peace talks, Colombia's President Gustavo Petro said on Tuesday.

Colombia has suspended peace talks with the National Liberation Army, or ELN, after blaming the rebel group for an attack that killed two soldiers and injured more than 20.