Brazil’s president Jair Bolsonaro has authorised the use of the military to battle the huge blazes sweeping parts of the Amazon while thousands took to the streets to protest his environmental policies.
Brazilian forces will deploy to border areas, indigenous territories and other affected regions in the Amazon from Saturday to assist in putting out fires for a month, according to a presidential decree authorising use of the army.
The military will “act strongly” to control the wildfires, Mr Bolsonaro promised as he signed the decree.
The armed forces will collaborate with public security and environmental protection agencies, the decree says.
“The protection of the forest is our duty,” the president said.
“We are aware of that and will act to combat deforestation and criminal activities that put people at risk in the Amazon.
“We are a government of zero tolerance for crime, and in the environmental field it will not be different.”
Mr Bolsonaro has previously described rainforest protections as an obstacle to Brazil’s economic development, sparring with critics who note that the Amazon produces vast amounts of oxygen and is considered crucial for efforts to contain climate change.
As the president spoke, thousands of Brazilians demonstrated in Rio de Janeiro, Sao Paulo and the capital of Brasilia demanding the government announce concrete actions to curb the fires.
People also banged pots from their homes, a traditional mode of protest in South America.
Small numbers of demonstrators gathered outside Brazilian diplomatic missions in Paris, London, Geneva and Bogota, Colombia, to urge Brazil to do more to fight the fires.
Larger protests were held in Uruguay and Argentina. Hundreds also protested in Chile, Ecuador and Peru.
Neighbouring Bolivia and Paraguay have also struggled to contain fires that swept through woods and fields, in many cases set to clear land for farming.
About 2,900 square miles of land has been affected in Bolivia, Defence Minister Javier Zavaleta said.
A B747-400 SuperTanker arrived in Bolivia and began flying over devastated areas to help put out the fires and protect forests. The US-based aircraft can carry nearly 76,000 litres (20,000 gallons) of retardant, a substance used to stop fires.
Some 140 square miles have burned in northern Paraguay, near the borders with Brazil and Bolivia, said Joaquin Roa, a Paraguayan state emergency official. He said the situation had stabilised.
Close to 20% of the Amazon has already been deforested, said Thomas Lovejoy, a George Mason University environmental scientist.
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US president Donald Trump said on Friday that he had spoken with Mr Bolsonaro.
“Our future Trade prospects are very exciting and our relationship is strong, perhaps stronger than ever before,” Mr Trump tweeted. “I told him if the United States can help with the Amazon Rainforest fires, we stand ready to assist!”
In escalating tension over the fires, France accused Mr Bolsonaro of having lied to French leader Emmanuel Macron and threatened to block a European Union trade deal with several South American states, including Brazil. Ireland joined in the threat.
Ahead of this weekend's G7 summit in Biarritz, France, Mr Macron’s office questioned Mr Bolsonaro’s trustworthiness.
Argentina, which is struggling with rising poverty and austerity measures, has offered to send emergency workers to Brazil and Bolivia to help battle the fires. Chile also offered aid.
The Brazilian government has said European countries are exaggerating Brazil’s environmental problems in order to disrupt its commercial interests.
Mr Bolsonaro, who has said he wants to convert land for cattle pastures and soybean farms, said it was difficult to curb increasing deforestation with limited resources.
“It’s not easy to fight deforestation, our Amazon area is bigger than all of Europe,” he said. “We’ll do what we can to fight this crime.”