US Secretary of State Condoleezza Rice has called for greater intervention by the Organization of American States in promoting democracy in Latin America.
Rice opened the summit with a call for democracy
Opening an OAS summit in Florida, she highlighted concerns over political crises in Bolivia, Ecuador and Haiti.
Private groups and individuals should be able to raise concerns with the OAS to help monitor democracy, she said.
But Venezuelan President Hugo Chavez accused the United States of seeking to impose a "global dictatorship".
"So, they're going to try to monitor the Venezuelan government through the OAS, they must be joking!" he said, speaking in Caracas shortly before the conference opened on Sunday.
"If there is any government that should be monitored by the OAS, then it should be the US government," he added.
Purpose, not ideal
Ministers from 34 Latin American and Caribbean nations are in Fort Lauderdale, Florida to discuss the region's most pressing problems.
Rice backed the new OAS Secretary General Jose Miguel Insulza
Ms Rice said: "When you look at some of the fragile democracies that there are, it's very clear that the institution needs to be better capable of dealing with them."
There was also an appeal for the OAS to advance democracy where it was absent - a reference to Communist Cuba.
Cuba was suspended from the OAS in 1961, two years after President Fidel Castro came to power.
"We must never, never accept that democracy is merely an ideal to be admired instead of a purpose to be realized," said the US secretary of state.
President George W Bush will address the conference on Monday.
He is expected to push a free trade agreement between the US, Central America and the Dominican Republic, known as Cafta.
Nearly all Latin American countries have moved from dictatorship to democracy over the last three decades - but elected governments have still been liable to fall or be overthrown.
Ms Rice said she had confidence that the new OAS Secretary General Jose Miguel Insulza, of Chile, could help bring about a change in fortunes for the region.
The US had originally backed Mexican Foreign Minister Luis Ernesto Derbez for the job, but he lost out when the organization came to vote for its new leader last month.
The rhetorical clash with Venezuela was expected, but she will further rile President Chavez when she meets a fierce opponent of his government, Maria Corina Machado, on Monday.
The two countries are also expected to clash over the fate of the terror suspect Luis Posada Carriles.
Venezuela wants him extradited for alleged involvement in the bombing of a Cuban plane in 1976, in which 73 people died.
The US has so far only charged him with immigration offences.
US government officials said prior to the meeting there would be no attempt to provoke a dispute with Caracas at the OAS summit.
Ms Rice met Venezuelan Foreign Minister Ali Rodriguez at a private event prior to the official opening of the conference.