The National Reserve of Copper and Associates (Renca) occupies roughly 17,800 square miles (46,100 square kilometers), an area slightly larger than Denmark, that is thought to be rich in gold, copper, iron ore and other minerals.
"Let's talk about Renca. Renca is ours," Bolsonaro said at a televised event in northern Amapá state, home to part of the reserve.
"Let's use the riches that God gave us for the well-being of our population," Bolsonaro said. "You won't get any trouble from the Environment Ministry, nor the Mines and Energy Ministry nor any other because our ministries, for the first time in the Republic, all understand and speak the same language: A better Brazil for all of us."
Mining has been off limits in the Renca, located in the northern states of Pará and Amapá, since it was established in 1984 to protect against perceived threats from foreign miners.
The reserve was established by a presidential decree and therefore can be revoked by the president without Congressional approval.
Bolsonaro's predecessor, Michel Temer, abolished the reserve in 2017, only to reinstate it the following month after an international backlash from environmentalists who said it would lead to a spike in deforestation.The Amazon, about 60 percent of which lies in Brazil, is the world's largest tropical rainforest. It is a bulwark against global warming and is sometimes called the "lungs of the world" because of the vast amounts of carbon dioxide its trees absorb.