SAO PAULO — The Brazilian government said Monday it would revoke a decree signed by leftist President Luiz Inácio Lula da Silva that allowed private concessions for waterways, following 33 days of protests by thousands of Indigenous people at a Cargill facility in Santarem in northern Brazil.

The decree authorized the government to assess the concession of waterways to private operators, including the responsibility for maintenance, dredging and vessel‑traffic management.

The decision marks a major victory for the Indigenous movement, which argued that dredging projects threaten the Tapajos River, Indigenous territories and the ecological balance of the world’s largest rainforest.

The Amazon plays a critical role in regulating the climate far beyond South America. Scientists warn that continued forest loss could accelerate global warming and disrupt agriculture as far away as the U.S. Midwest and parts of Europe.