Coelho, who will replace retired army general Joaquim Silva e Luna in the job, is set to take office later on Thursday.

The move comes right after the company voted Coelho onto its board, paving the way for the government technocrat to take the helm of the firm, as under Petrobras' statutes the chief executive must be on the board to get elected.

Coelho, who previously served as the secretary of oil, gas and biofuels at Brazil's Mines and Energy Ministry, was tapped for the role earlier this month after energy consultant Adriano Pires backed out of the government's nomination.

(Reporting by Gabriel Araujo; editing by Diane Craft)