Magda Chambriard, a former Brazil oil regulator, also said she does not support taking back divested oil refineries and other assets or using Petrobras' profits to subsidize consumer fuel prices.
Lula, who spent time in jail over a Petrobras corruption scandal, campaigned on abandoning further privatization of Petrobras, and on investing in diversification.
Petrobras has sold oil refineries, retail gas stations, power plants and gas pipelines to pay debt and boost its shareholder payouts.
Like Lula, she believes the way to guarantee Petrobras' future in a world determined to cut planet-warming emissions should include developing less carbon-intensive fuels, such as natural gas.
Some of the dividends Petrobras distributed this year should be redirected to energy production, including exploration of new oil and gas fields, she said.