Displaying deep annoyance, Chavez asked hypothetically in his comments before the National Assembly what would happen if oil-exporting Venezuela cut off shipments to the United States.
Chavez also accused a U.S. Jewish rights group of joining a Washington-backed smear campaign after it denounced him for making anti-Semitic remarks. Chavez insisted those remarks had nothing to do with Jews and were badly misconstrued.
His comments came after the U.S. Embassy in Madrid announced that the United States had denied permission for the sale of planes, citing concerns about a Venezuelan government that it said had "grown progressively more autocratic and antidemocratic."
"What is this if not evidence of the horrific imperialism that the government in Washington wants to impose on the world?" Chavez said.
In Washington, State Department spokesman Sean McCormack said the United States concluded the proposed transfers were not consistent with the country's interests.
"We're concerned that this proposed sale of military equipment and components to Venezuela could contribute to destabilization in Latin America and have made that view clear to the Spanish, Venezuelan and other governments in Latin America," McCormack said.
Chavez has accused the United States of plotting to overthrow him and has warned any invasion would be defeated. Washington has strongly denied any such plans, but Chavez says Venezuela, the world's No. 5 oil exporter whose main customer is the United States, must be prepared.
"Every day we send them 1.5 million barrels of oil," said Chavez. "What would happen if tomorrow I were to say that no ship leaves for the United States?"
He made it clear the idea was not being considered at present, but was possible if the United States tried to oust him.
U.S. law authorizes the government to prevent a country from transferring military equipment purchased in the United States to a third country.