Venezuela says it will encourage investment by private companies in part of the country's oil-rich Orinoco River basin.
Oil Minister Rafael Ramirez says investment in each of three oil fields will be about US$8 billion (euro5 billion).
He says the main aim is building heavy crude upgrader plants in partnership with the state-run Petroleos de Venezuela SA. The company said in a statement Thursday that it will soon announce a bidding schedule.
President Hugo Chavez's government took majority control of the last remaining privately run oil projects last year.
U.S.-based Exxon Mobil Corp. operated in the eastern Orinoco area before pulling out last year. Other oil companies accepted tougher terms to stay on as minority partners.
