PETROLEO Brasileiro, Brazil's state-owned oil company, says it may become the world's third-biggest oil refiner with a plan to build two new plants.

The two refineries in Rio Grande do Norte and Ceara states, along with plants under construction or being planned, will boost refining capacity by at least 1 million barrels a day by 2014, the company said. This would put it in third place behind Exxon Mobil and Royal Dutch Shell, it said.

Petrobras, currently ranked sixth by capacity, plans to make more higher-value fuels for sale in the United States and other markets. The Rio de Janeiro-based refiner earns more from exports as the Brazilian government, to curb inflation, hasn't allowed the prices of oil products to rise in step with crude oil, Bloomberg News said.

Petrobras said it may build a refinery in Ceara to process 300,000 barrels a day by 2014. The facility will produce low-sulfur gasoline and other fuels that meet US environmental standards. The refinery will complement a plant planned for Sao Luis, which is expected to process as much as 500,000 barrels a day into low-sulfur fuels for export.

The company, which can process 2.17 million barrels a day, is also building a 200,000-barrel-a-day heavy-oil refinery near Recife and a 150,000-barrel-a-day petrochemical refinery near Rio de Janeiro.

Petrobras didn't say how much oil the refinery in Rio Grande do Norte would process. The facility would produce diesel, the most-used vehicle fuel in Brazil, and commence production in 2010.

Brazil, which became a net oil exporter for the first time last year, is also one of the world's largest oil consumers.