Brazilian state-run oil firm Petrobras is considering putting additional stakes in significant offshore oilfields up for sale, executives said on Wednesday, as the company continues to aggressively de-leverage.

In a presentation, the executives said they may sell stakes in the Marlim field, as well as the firm's majority stake in the Papa-Terra field, both located in Brazil's offshore Campos Basin.

Roberto Castello Branco, chief executive of Petroleo Brasileiro SA, as the firm is formally known, said parts of Marlim could fetch between $2 billion and $4 billion.

(Reporting by Rodrigo Campos; Writing by Gram Slattery; Editing by Bill Berkrot)