U.S. officials have repeatedly denied any military plans against Chavez, but also call him a threat to stability in the region.

Speaking to other South American leaders, Chavez said his conflict with Washington is rooted in the U.S. thirst to control oil. He said the Americans will be denied that in Venezuela, which is the world's fifth-largest oil exporter and one of the biggest suppliers to the U.S. market.

If the United States attacks, Chavez said, "We won't have any other alternative - blow up our own oil fields - but they aren't going to take that oil."

Some of Chavez's political opponents at home call his warnings about a U.S. invasion far-fetched and contend he pursues the verbal conflict with Washington to encourage a sense of struggle against a foreign enemy as he heads toward the presidential election in December.

Chavez cited what he called a regular flow of threatening statements and actions from the U.S. government, from U.S. naval exercises being held this month in the Caribbean to U.S. questions about Venezuela's deepening ties with Iran.

"The latest they've invented is that we're sending uranium to Iran, and what's more yesterday it came out in the Venezuelan press that we're making a secret plan to bring Iranian nuclear missiles and install them in Venezuela," he said.

In that report, the Venezuelan newspaper 2001 cited unidentified U.S. intelligence sources as saying Iran and Venezuela made a secret deal to ship missiles to Venezuela and Cuba aboard oil tankers. It did not provide any details about its sources, and the report was roundly denied by Venezuelan officials as preposterous.

Chavez accused the United States of "searching for an excuse for anything" against Venezuela, noting U.S. warship are holding exercises this month in the Caribbean - "there under our very noses."

In Caracas, meanwhile, Venezuela's defense minister, Adm. Orlando Maniglia, said Chavez's military plans to hold its own exercises soon along the coasts and with neighboring countries' armed forces.

"We already have planned some future exercises with the government of Curacao, and also with the Dutch, with the navy and armed forces of Colombia," he said, without giving any details.'

But Venezuela also has problems with neighboring Colombia. It demanded Wednesday that Colombian President Alvaro Uribe investigate a Colombian magazine's allegations that Uribe's secret police plotted to assassinate Chavez.

"The government of President Uribe is obligated to thoroughly investigate and share its investigation with the Venezuelan government," Vice President Jose Vicente Rangel told reporters in Caracas.

Uribe has denied the accusations.