In a bid to augment returns on its expanding output of oil and natural gas, Brazil's state-controlled oil major Petroleo Brasileiro SA (Petrobras) is reportedly considering up-scaling its petrochemicals investment for 2008-2012. The company had initially planned US$8.6 bln for petrochemical expenditure which is projected to rise as the company seeks to up its refinery business. The company's offshore exploration has led to the Western Hemisphere's biggest discovery in 30 years by the discovery of Tupi field in 2006 (off the coast of Brazil in Santos basin), containing roughly 8 bln barrels of oil. The company is progressing with growth of the offshore fields, where production is still feasible at current oil prices and its output costs are sub-US$40/barrel. The company has taken US$35/barrel as a reference price in its 2008-2012 investment plan.