As an agricultural powerhouse, Brazil has a huge demand for fertilizers. Many of them are potassium-based, and much of it is sourced in Russia and Belarus.

The conflict in Ukraine disrupted the flow of this important mineral and led to calls by Brazilian farmers and politicians for strategies to increase domestic production.

President Bolsonaro himself was vocal in saying that Brazil needs to open protected indigenous lands in the Amazon for potassium exploration.

But environmentalists and activist groups object.

Correspondent Paulo Cabral travelled to the Amazon to investigate.