Brazil sees "surprising" deforestation drop in Amazon
Brazil said deforestation in the Amazon rainforest has dropped by 18% in the past year.
Environment Minister Izabella Teixeira said the fall, for the year ending July 2014, meant deforestation was at its second lowest level in 25 years.
But campaigners say alternative monitoring shows an increase for a second year running.
In 2012 the government eased restrictions on landowners, weakening legal protection for the rainforest.
Ms Teixeira said 4,848 square kilometres (1,872 square miles) of rainforest were destroyed between August 2013 and July 2014.
The figure was down from 5,891 kilometres (2,275 square miles) during the same period a year earlier.
But a spokesman for the World Wide Fund for Nature said alternative satellite monitoring systems, not used by the government, in fact suggested an increase in the rate of forest destruction for a second year running.
A non-government group, Imazon, which uses satellite pictures to measure deforestation warned last week of a 467% rise in October from the same month a year earlier.
But Ms Teixeira said the official estimate was the most accurate: "Anything else is speculation. We have been working hard to end deforestation."
She presented the figures just days before the Lima Climate Change Conference, which opens on Monday.