The inquiry, by government lawyers, is the first step in a process that could see Venezuela join North Korea, Cuba, Sudan, Syria and Iran as countries designated by the State Department as supporters of terrorism.

U.S. laws permit some leeway on the scope of sanctions, but experts say that adding Venezuela to the list could force U.S. and even foreign firms to sever or curtail links with one of the world’s leading oil producers and the owner of Citgo Petroleum.

The inquiry comes after Colombia seized four computers belonging to a guerrilla leader in a March 1 raid into Ecuador. The documents suggest Venezuela, among other things, promised $300 million to the Revolutionary Armed Forces of Colombia, or FARC.

The U.S. and Colombian governments and the European Union have officially designated the FARC as a terrorist organization, but Venezuelan President Hugo Chávez has said publicly that he considers it a legitimate insurgency.