In a move to prepare for possible oil drilling in Cuba, Brazil's state-controlled energy giant Petrobras opened an office in Cuba, the company announced Thursday.

As part of its exploratory stage, Petrobras is currently analyzing results of seismic surveys carried out within the block it acquired last October in the communist-ruled country's waters of the Gulf of Mexico.

According to the terms of its contract with Cupet, Cuba's state-owned oil company, Petrobras has until May 2010 to decide whether to begin drilling.

Joao Figueras, CEO of Petrobras' Venezuelan arm, said the Havana office is "a point of reference" during the first exploratory phase, the Latin American Herald Tribune reported. Then, if Petrobras decides to advance to the drilling stage, it will further expand its representation in Cuba, he said.

Petrobras attempted to search for oil in the country's territorial waters between 1998 and 2001. "It was a perfect operation, but unfortunately the well was dry," acknowledged Figueras, who also heads up the company's new Cuba office.

Currently Petrobras has a 32-year exploration and production agreement with the Cuban government, allowing it to operate in a 617-square-mile block "very well located from a geological point of view," Figueras said.

"If we make the decision to drill, the company will have the means to carry out the drilling," he pointed out. "That's why our job now is to be very focused on the geophysical-geological work so that we make the best decision."

Cuba produces the equivalent in oil and gas of 75,000 barrels per day, around 50 percent of its energy needs. It imports the rest from oil-rich Venezuela.

According to Cupet's estimates last November, there are 20 billion barrels of offshore oil in the communist country's waters in the Gulf of Mexico. That puts Cuba among the world's Top 20 countries in terms of oil reserves. But the U.S. Geological Survey's 2004 estimate is far lower, ranging from 5 billion to 10 billion barrels.

Petrobras is not the only oil explorer operating in Cuba's territory of the Gulf of Mexico known as the Exclusive Economic Zone, which covers more than 43,000 square miles. Cuba has also awarded oil and gas exploration leases to companies from Canada, Spain, Norway, China, India and Venezuela.

Petrobras, an integrated energy company and a global leader in deepwater oil exploration and production, operates in 27 countries in the Americas, Africa, Asia and Europe.

It produces more than 80 percent of Brazil's oil from offshore fields.