Jan. 23 (Bloomberg) -- Petroleo Brasileiro SA, Brazil's state-controlled oil company, said the Tupi gas field may be ``only one indication'' of the potential reserves on offer at a recent discovery.

Tupi, one of the world's biggest finds of the past 30 years, could be followed by other discoveries in the region, Chief Executive Officer Jose Sergio Gabrielli said today in a Bloomberg Television interview from Davos, Switzerland.

``We are still talking about preliminary data but the indications point to big volumes,'' Gabrielli said. ``We think that we have a very large, new exploratory frontier in the coast of Brazil.''

Rio de Janeiro-based Petrobras, as the company is known, said earlier this week that it found another natural-gas field that may rival Tupi in size. Jupiter would be the second giant strike reported by Petrobras in the past 10 weeks. Tupi has as much as 8 billion barrels of oil and gas, three quarters of the reserves of Kazakhstan's Kashagan field, the largest oil discovery in the last 30 years.

The latest finds may offer Brazil the opportunity to overtake Mexico and Venezuela as one of the biggest oil producers in Latin America, Gabrielli said.

Petrobras expects a new regulatory model on exploration concessions to attract more foreign companies to the country, Gabrielli said.

There's unlikely to be an ``excessive'' drop in oil prices as a result of the U.S. economic slowdown, and so Petrobras has no need to revise its investment plans, Gabrielli said.

To contact the reporter on this story: Telma Marotto in Sao Paulo at Tmarotto1@bloomberg.netJoao Oliveira in Sao Paulo at joliveira4@bloomberg.net

Last Updated: January 23, 2008 06:28 EST