Brazilian state-run energy giant Petroleo Brasileiro (PBR, PETR4.BR), or Petrobras, plans to double its crude production from the current level to four million barrels a day by 2020, said its chief executive Jose Gabrielli Monday.

"We are sitting on 35 billion barrels of reserves...we'll have the biggest new supply outside of OPEC (Organization of Petroleum Exporting Countries)," he said in an industry event.

Also, Petrobras will look to invest in the production of ethanol and second-generation biodiesel, Gabrielli said.

The CEO's latest remarks are in line with the company's earlier statements.