Venezuelan President Hugo Chavez has recalled his ambassador to Colombia and frozen bilateral relations in a dispute concerning weapons that ended up in the hands of Colombian FARC rebels.
There was no immediate response from Colombia.
President Chavez made the announcement Tuesday during a televised meeting with his aides. The dispute with Colombia stems from Bogota's claim that anti-tank rocket launchers sold to Caracas were obtained by the FARC, which is Colombia's main rebel group.
The weapons were made in Sweden, which has asked Venezuela to explain how they made their way to the rebel group.
Colombian Vice President Francisco Santos has said the launchers were found in a captured arms cache belonging to the FARC. Venezuela rejected the report as untrue.
Colombia's government has been at war with the FARC since the 1960s. Colombia, the European Union and the United States have designated the group as a terrorist organization.
Separately, the FARC is denying accusations that it gave money to the 2006 political campaign of Ecuadorean President Rafael Correa.
The rebel group also alleges that Colombia and the United States manipulated a video, released earlier this month, in which a top FARC commander said the guerrillas helped fund the Correa campaign.
President Correa has previously dismissed the video as a fake and denied accepting money from the rebels. He has said, however, that the rebels may have been deceived by someone who falsely told them the funds would go to the presidential campaign.
Some information for this report was provided by AFP, AP and Reuters.