The comments are likely to increase pressure on Brazil's government to rein in deforestation. Brazil is the world's largest Catholic country and the church remains highly influential despite falling membership.

Werlang's warning follows disagreement within the government of President Luiz Inacio Lula da Silva over increasing Amazon deforestation rates.

The environment ministry has blamed farmers and cattle ranchers for moving deeper into the forest in search of cheap land, while Lula and the agriculture ministry reject the charges. Between August and December an estimated 2,703 square miles (7,000 square km), or two-thirds the annual rate for the 12 months ending in July 2007, were chopped down.

Increased sugar cane production, the raw material for the country's much-touted ethanol program, also drives crops and cattle further north into the Amazon, environmentalists say.

"We have to question the energy programs that deteriorate our rivers and land with the construction of ever more hydroelectric plants and monoculture farm production," said Werlang, member of the Brazilian Bishops Conference CNBB. Part of its campaign this year in defense of life aims to raise environmental awareness.

The Lula government tendered in December the right to build a US$5 billion hydroelectric plant, the first of two along the Madeira river in the western Amazon.

Friends of the Earth, an environmental advocacy group, estimates that the project could attract as many as 100,000 settlers to the region, increasing pressure on land and natural resources.