Petrobras (PBR)

Third well indicates Tupi potential

(Rio de Janeiro, June 4, 2009). – PETRÓLEO BRASILEIRO S/A - PETROBRAS, [Bovespa: PETR3/PETR4, NYSE: PBR/PBRA, Latibex: XPBR/XPBRA, BCBA: APBR/APBRA], a Brazilian international energy company, announces that the drilling of an additional well in the Tupi area has further confirmed estimates of a potential of 5 to 8 billion barrels of recoverable light oil and natural gas in the pre-salt layers of that field. Drilling is still underway seeking for other objectives at greater depths.

The third well, 4-BRSA-711-RJS (4-RJS-647), is located 33 km to the Northeast of Tupi first well, 1-RJS-628, and indicated similar oil type and quality reservoirs, supporting the original estimations for the area.

Informally known as Iracema, this well is located about 250 km off the coast of the state of Rio de Janeiro at a water depth of 2,210 meters, following the Tupi Evaluation Plan.

The discovery was proved from light oil samples (about 30º API) through cable testing in reservoirs located at a depth of about 5,000 meters and having been notified to the National Petroleum Agency (ANP) today.

Following the conclusion of the drilling, the Consortium composed by Petrobras (65% - Operator), BG Group (25%) and Galp (10%), jointly responsible for the exploration of the BM-S-11 Block, will continue activities and investments forecasted in the Evaluation Plan approved by ANP, which also considers the drilling of other wells in the area.

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