CARACAS, Venezuela —  Venezuelan President Hugo Chavez accused the United States on Wednesday of using anti-drug flights for spying — and said that fighter jets are ready to defend Venezuela's sovereignty.

Chavez said a U.S. Navy plane that flew into Venezuelan airspace during a purported anti-drug mission was actually involved in reconnaissance.

"They are spying, even testing our capacity to react," Chavez said in a televised speech. "We are not going to allow the violation of our sovereignty."

The U.S. Navy plane was detected by Venezuelan authorities Saturday near the Caribbean island of La Orchila, and its crew was questioned over the radio by Caracas' airport control tower.

Chavez said that pilots who fly Venezuela's SU-30 Sukhoi combat jets, newly bought from Russia, were "starting their engines" shortly after the U.S. Navy plane was detected.

U.S. government officials say the S-3 Navy plane was on a counter-drug mission when it accidentally strayed into Venezuelan airspace due to a navigational error.

The incident has aggravated U.S.-Venezuelan tensions.

A U.S. Embassy spokeswoman in Caracas did not immediately return a message seeking comment on Chavez's statements. U.S. officials have dismissed the Venezuelan leader's past spying accusations.

Chavez also reacted angrily on Wednesday to Washington's concerns that his government could be aiding Colombian rebels.

Colombia says files retrieved from a slain rebel leader's computers show Venezuela sought to finance and arm the Revolutionary Armed Forces of Colombia, or FARC. Chavez strongly denies it, saying Venezuela's contact with rebels has been aimed only at securing the release of hostages.

"The only thing that has motivated us to contact them is the humanitarian agreement," Chavez said. "The United States — the world's principal terrorist state — wants to include us on the list" of countries it accuses of sponsoring terrorism.

Some U.S. lawmakers want Venezuela on the list, along with countries including Iran and North Korea. But that could involve economic sanctions — a potentially risky move against America's fifth-largest oil supplier.