Chevron said the videos "reveal a three-million-dollar bribery scheme implicating the judge presiding over the environmental lawsuit" against it, in a statement.
The oil giant claimed that judge Juan Nunez met in May and June with a man supposedly acting on behalf of the ruling Alianza Pais party, Carlos Garcia, and two businessmen.
Ecuador's government on Tuesday denounced the corruption claims.
"Unfortunately, Chevron, through its lawyers, is benefiting from a crime of intercepting conversations without authorization, with the aim of damaging Ecuador," Alexis Mera, a secretary of judicial affairs in the president's office, said in a statement.
Chevron said the tapes show them discussing a "commission" of three million dollars to be paid once a sentence against Chevron had been handed down.
But Mera said the Ecuadoran government is "not part of the litigious process that several Amazon communities brought against Chevron, so there was no past, current, nor will there be any involvement in that process."
Chevron has rejected a court report holding it liable for 16.5 billion dollars in alleged environmental damage when Texaco, acquired by Chevron in 2001, was extracting crude in the Amazon jungle between 1964 and 1990.
Several of Ecuador's indigenous communities filed a class-action lawsuit against Chevron in 2003 seeking compensation for soil pollution in their Amazon homelands.
Quito has also sued Chevron for widespread contamination allegedly caused by the Texaco subsidiary's oil-drilling operations in Amazon territories before the subsidiary was sold to Ecuador's state-run oil company Petroecuador.
An expert's conclusion -- in a finding disputed by Chevron -- was that 27.3 billion dollars in environmental damage had been done.
The Amazon Defense Coalition has led a 27-billion-dollar compensation claim on behalf of dozens of rainforest communities and five indigenous groups.
The coalition says some 18.5 billion gallons of contaminated water was dumped in the Amazon waterways, pits were filled with toxic sludge and at least 17 million gallons of crude oil were spilled, affecting 30,000 rainforest residents.
Chevron's videos purport to show that judge Nunez in Lago Agrio confirms to the businessmen that a sentence is almost ready -- for October -- and that the Ecuadoran government will decide who will do cleanup work and how.
The businessmen are named as Diego Borja and Wayne Hansen, and they tell the Ecuadorans on the video they are interested in cleanup work.
"Of the three million (...) a million for the judge," Borja says in the recording purportedly from June 22, 2009.
"Yes," says Garcia, the supposed ruling party operative.
"A million for the president's office," Borja then says.
"Yes," Garcia says again.
"And a million for the plaintiffs," Borja says.
"That's it," Garcia says.
In a statement, Chevron said it "has consistently asserted that the case has involved improper complicity between the plaintiffs and Ecuador's executive branch and other legal irregularities."
In 1990, a New York court ordered Texaco to stand trial in Ecuador on environmental charges, the first time a US oil company was told to answer to charges in a foreign country.
Story by AFP/09/01/2009 / Video source Chevron
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