The bill, already passed by Brazil's Senate, will now move to the full lower house in Brasilia for a vote expected as early as next week.
The pre-salt province, off Rio de Janeiro, contains about 100 billion barrels of untapped resources, according to Rio de Janeiro State University.
The bill would modify a 2010 law requiring all new pre-salt development to be led by Petrobras, and that the state-owned producer take a minimum 30% financial stake in all such projects.
