 The vast majority of proven reserves were located in the Campos and Santos offshore basins off the southeast coast of Brazil.In November 2007, Petrobras announced that it believed the offshore Tupi oil field had between 5 and of recoverable light oil and neighbouring fields may even contain more, which all in all could result in Brazil becoming one of the largest producers of oil in the world.Brazil has been a net exporter of oil since 2011.