Total’s application to drill near the Amazon Reef has been rejected.
The decision from the Brazilian Environmental Agency destroys the French energy giant’s long-standing plans to drill in the region.
Environmentalists claim around 1.2 million people around the world have protested against the plans at various stages.
The agency said Total had not provided adequate information about the environmental impact the project would have on what is a unique and largely unexplored ecosystem, making it impossible to grant the license.
The company itself calculated the chance of the reef being affected in the event of an oil spill at nearly a third.
Total now has a final chance to send additional documentation before the application will be permanently closed.
Helena Spiritus, Greenpeace Brazil Energy Campaigner, said: “The only right decision by Total now is to give up their plans to drill at the Amazon mouth, instead of trying to find ways to convince authorities to approve this risky project, rejected by science, local communities and by the Brazilian Environmental Agency.”