Venezuelan President Hugo Chavez must explain documents found on Colombian rebel computers that Washington and Bogota charge show deep ties between the leftist leader and the guerrillas, a top U.S. official said.
Interpol last week said its forensic tests showed the authenticity of the files but the international police agency could not vouch for the veracity of the contents of the computers found at a FARC rebel camp inside Ecuador in March.
Chavez and Ecuador's Rafael Correa, who Colombia says the files show also maintained rebel ties, dismiss accusations as lies and part of a U.S.-backed campaign to discredit them based on unsubstantiated documents.
"President Chavez has a lot of explaining to do," White House drug czar John Walters told Colombian newspaper El Tiempo in a Spanish-language interview published on Sunday.
"They were fluid contacts from both sides. This is a group that wants to violently overthrow a democratic government. This is very serious and requires more than just a simple denial."
Accusations based on the files from three laptops, hard drives and computer data keys are fuelling diplomatic tensions in the Andean region, where Colombia's President Alvaro Uribe is Washington's closest ally and Chavez its fiercest critic. Colombian forces found the computers when they swept across the Ecuadorean frontier to kill a top FARC commander. The operation sparked a regional crisis with Ecuador and ally Venezuela sending troops to their borders with Colombia.
The FARC or Revolutionary Armed Forces of Colombia, has been weakened by Uribe's U.S.-backed security campaign. But the rebels, labelled terrorists by U.S. and E.U. officials, are still fighting with help from cocaine trafficking. The charges Colombia has made based on the files have fostered calls by some in the U.S. Congress to implement sanctions against Chavez, a former soldier who the United States has often labelled a menace to regional stability.