State-owned Brazilian oil company Petrobras said Thursday it had discovered up to 700 million barrels of oil and natural gas in the Gulf of Mexico, the company said in a statement.
Petrobras, which shares the discovery with Exxon Mobil, called the oil fields "one of the greatest discoveries in the Gulf of Mexico in the last decade."
The oil was located in two blocks some 400 kilometers (240 miles) southwest of New Orleans, at a depth of 2,100 meters (6,930 feet).
Brazil has spent the past several years investing in deep water drilling technology.
In March, Petrobras received permission from the United States to begin deep water oil and natural gas production in the Gulf of Mexico.
Less than a year earlier, on April 20, 2010, a BP oil drilling platform in the Gulf exploded, killing 11 workers and spilling nearly five million barrels of oil in one of the worst environmental disasters in US history.