French President Emmanuel Macron has said the record number of fires in the Amazon rainforest is an "international crisis" that needs to top the agenda at this weekend's G7 summit.
"Our house is burning," he tweeted.
Brazil's President Jair Bolsonaro responded by accusing Mr Macron of using the issue for "political gain".
He said calls to discuss the fires at the G7 summit in Biarritz, which Brazil is not participating in, evoke "a misplaced colonialist mindset".
The largest rainforest in the world, the Amazon is a vital carbon store that slows down the pace of global warming.
Satellite data published by the National Institute for Space Research (Inpe) has shown an increase of 85% this year in fires across Brazil, most of them in the Amazon region.
Russia's unmanned Luna-25 spacecraft has crashed into the Moon after spinning out of control, officials say.
Donald Trump has confirmed that he will not take part in Republican presidential debates with his rivals in the race for the White House.