Rosales was arrested in October 2015 upon his return to Venezuela from exile in Peru, six years after the government of the late socialist leader Hugo Chavez accused him of illicit enrichment.
Under current president Nicolas Maduro, opposition figures including protest leader Leopoldo Lopez have been jailed on the grounds of stoking violence to overthrow his leftist administration. Opposition activist Francisco Marquez, who was jailed in June on money-laundering charges, was released this week.