Brandishing a photo of the plane, which he described as a P-3, Chavez said the overflight was the latest violation of Venezuelan airspace by the U.S. military from its bases on the Netherlands' Caribbean islands and from neighboring Colombia.

"They are provoking us ... these are warplanes," he said.

Chavez said the F-16s escorted the U.S. plane away after two incursions lasting 15 and 19 minutes each.

A spokesman for the U.S. Defense Department denied Chavez's assertion, saying in an e-mail: "We can confirm no U.S. military aircraft entered Venezuelan airspace today. As a matter of policy we do not fly over a nation's airspace without prior consent or coordination."

Senior Obama administration officials said the U.S. Southern Command was unaware of any incident involving U.S. government aircraft in Venezuelan airspace on Friday.

The perceived threat of U.S. intervention has become a central element of Chavez's political discourse and a rallying cry for his supporters.

Foes say Latin America's loudest U.S. critic is hyping the idea of a foreign threat to distract Venezuelans from domestic problems such as economic recession, rampant crime and inadequate public services.

The socialist leader surprised the diplomatic world in December when he accused the Netherlands of abetting potential offensive action against his government by granting U.S. troops access to its islands close to Venezuela.

The Dutch government says the U.S. presence on Curacao and Aruba -- where about 250 Air Force crew and ground staff are based -- is only for counternarcotics and surveillance operations over Caribbean smuggling routes.

(Reporting by Frank Jack Daniel; Additional reporting by Doug Palmer; Editing by Peter Cooney)