Venezuelan President Hugo Chavez said the U.S. Navy's decision to re-establish its Fourth Fleet is "a threat" to Latin America.
Chavez wants the South American trade bloc Mercosur to ask the U.S. government why it is sending the military force to a peaceful region.
Washington said the fleet will maintain security and carry out military exercises, humanitarian missions and drug operations.
But Chavez sees darker purposes — such as an attempt to control the Amazon river and other interior waterways.
The Fourth Fleet was active during World War II but dissolved in 1950. The U.S. Navy has decided to re-establish the fleet to direct naval forces in the Caribbean and Latin America.