Around 360 square kilometres of rainforest in the Brazilian Amazon were lost to deforestation in January alone.
This is the highest amount recorded for January since 2015, the National Institute for Space Research (Inpe) said Wednesday, citing provisional figures.
Inpe uses satellite imagery for its analysis, using a rapid survey to examine the changes to the forest in real time.
The Inpe figures are therefore able to indicate how the official deforestation rate might develop in relation to a given year. The annual rate is for the period from August to July.
At the COP26 UN climate conference, the Brazilian government announced it would end illegal deforestation in the Amazon rainforest by 2028.
Experts fear the latest data could indicate an increased risk of another devastating year for the Amazon.
Between August 2020 and July 2021, some 13,235 square kilometres were deforested in the region, according to Inpe.
This marks a 22 per cent increase on the previous year, and the largest area of deforestation since 2008.
2019 was the first year in office for Brazilian President Jair Bolsonaro. The right-wing leader was criticized over the devastating fires in the Amazon.
Environmentalists accuse him of accepting the fires as a way to open up new land for agriculture. Brazil has also weakened its environmental and monitoring authorities.