CARACAS, Venezuela (AP) — A day after saying he hopes to eventually cool tensions with Colombia, President Hugo Chavez charged that his neighbor recently allowed a U.S. military plane to carry out “electronic warfare” operations against Venezuela.

Chavez told a crowd of soldiers Monday that his intelligence services detected the American aircraft that he said took off from a Colombian base and flew along the border between the two South American nations, which have seen long tense relations worsen in recent months.

Without giving details, he said Venezuela’s military intelligence intercepted a conversation between the pilot and air traffic controllers in the northern Colombian city of Barranquilla.

The aircraft conducted espionage operations, he said.

“Through our strategic intelligence, we detected an RC-12 airplane belonging to the U.S. Air Force,” Chavez said during a talk to an auditorium packed with military officers, rank-and-file soldiers and cadets.

“It was a plane specialized for electronic war, and it was carrying out electronic war operations,” he added.

U.S. Embassy spokeswoman Robin Holzhauer would not directly respond to Chavez’s accusation during a telephone interview on Monday, saying only that “the United States and Colombia engage in a number of bilateral activities,” all of which “respect the sovereignty of other nations.”

No one was immediately available at U.S. Southern Command in Miami to comment.

Chavez has made similar accusations in the past, saying in December that a U.S. military plane had entered Venezuelan airspace and was met by his military’s F-16s and escorted out. The P-3 plane took off from the Dutch Caribbean island of Curacao, he said.

The U.S. Southern Command denied it.

Chavez didn’t elaborate on the alleged spying incident, but the former paratrooper accused Colombia’s government of allowing the U.S. military to use its territory to mount what he called “an aggression” against Venezuela.

Relations between Venezuela and Colombia have been rocky for years, but frictions have intensified recently over Colombia’s agreement to give the U.S. increased access to its military bases — a deal that Chavez calls a threat to his country.

Colombia, meanwhile, accuses Chavez’s government of supporting Colombia’s Marxist rebels. Chavez rejects the allegation.

Chavez’s comments came a few hours after Colombia’s conservative president, Alvaro Uribe, accused the Venezuelan leader of meddling in Colombia’s presidential election campaign by trying to influence the outcome of the vote.

On Sunday, the socialist Chavez said he hoped for improved relations with Colombia’s next president, but warned that efforts to reduce tensions would face serious obstacles if Uribe’s ally — former Defense Minister Juan Manuel Santos — wins the May 30 election.

Chavez, who has repeatedly clashed with Uribe and Santos, also said Colombia’s government could become a threat to its neighbors if Santos was elected.

“It’s an insult to the Colombian people that a foreign government attempts to coerce their free political will to pick the next president,” Uribe said.

He accused Chavez of trying to “intimidate” Colombians by warning that a Santos victory could lead to armed conflict.

“The Colombian people are not going to accept this blackmail,” said Uribe, whose term ends Aug. 7.

Santos is among the favorites to win Colombia’s presidential election.

After lambasting Santos on Sunday, Chavez denied he is trying to influence the outcome of the vote.

• Christopher Toothaker