Brazil has banned setting fires to clear land for 60 days in response to a massive increase in the number of fires in the Amazon rainforest.
The decree was signed by President Jair Bolsonaro, who has faced intense criticism at home and abroad for failing to protect the rainforest.
A leading Brazilian environmentalist warned on Wednesday that the “worst of the fire is yet to come”.
South American countries will meet next week to discuss the crisis.
It remains unclear what impact the ban will have, as environmentalists say the overwhelming majority of forest clearance in the Brazilian Amazon is already illegal and enforcement is lax.
The Amazon – a vital carbon store that slows down the pace of global warming – has seen more than 80,000 fires break out so far this year – a 77% rise on the same period in 2018.
Environmentalists say the increase is due in part to policies enacted by Mr Bolsonaro’s administration.
Prosecutors have been investigating allegations that some of the fires were triggered by the illegal clearing of land and the decree now bans setting fires for this purpose across the entire country.
It allows three exceptions: when fires are authorized by environmental authorities for reasons relating to plant health; as a preventative measure to fight wildfires; and as part of traditional subsistence agriculture practiced by indigenous people.