Brasilia - Deforestation in Brazil's Amazonian rainforest cut down or affected 7,000 square kilometres this year, the lowest rate in more than two decades, the Brazilian government announced Thursday.

"This is by far the lowest at least since 1988," when monitoring began, said Gilberto Camara, head of the National Institute for Special Investigations (INPE).

The 12-month data, covering August 2008-July 2009.

The area is just more than a quarter of the 27,000 square kilometres deforested in 2004, when the trend began toward a gradual reduction in the rate of rain forest loss.

The latest year is a reduction of nearly 46 per cent from the August 2007-July 2008 period estimate of 12,911 square kilometres.

"Since 2004 we have detected a substantial fall in deforestation, with constant reductions over the past six years," Camara said. (dpa)