Eni said it uncovered a "supergiant" gas discovery at the Perla field in the Gulf of Venezuela.
"This well confirms Perla as a world-class supergiant gas discovery, one of the most significant in recent years and the largest ever in Venezuela, upgrading current estimates of gas in place to over 14 trillion cubic feet, or 2.5 billion barrels of oil equivalent," the company said in a statement.
Initial production testing of the well yielded 68 million cubic feet of gas and 1,350 barrels of condensate per day.
Natural gas makes up 34 percent of the hydrocarbons available in Venezuela. As of 2010, there were an estimated 176 trillion cubic feet of proven gas reserves there, placing it second in the Western Hemisphere behind the United States, the U.S. Energy Information Agency reports.
Around 90 percent of the natural gas reserves in Venezuela are associated with crude oil.