Speaking at the same event, which opened Saturday, Maduro's closest regional ally, Cuban President Raul Castro, echoed the charge, despite his country's thawing relations with the United States.

"Venezuela is facing an onslaught... that is against all of Latin America and the Caribbean, that is trying to re-impose and recolonize the politics, economy, culture and life of our countries," Maduro -- a socialist who has made the economy increasingly state-run -- charged in his speech after taking over the movement's rotating presidency from Iran.

Leaders from the 120-nation group, including Iranian President Hassan Rouhani, gathered for two days on Venezuela's Caribbean island of Margarita.