The country's Institute of Environment and Renewable Natural Resources, IBAMA, has issued the installation licence for the controversial mega-project, along with various social and environmental compensation schemes intended to mitigate its impact.
Protestors have vowed to continue fighting Belo Monte, which will be the world's third-largest hydro facility when completed on the Xingu river.
The hydropower project is expected to cost about R$19bn ($12bn), mostly financed via the Brazilian development bank BNDES.
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