A record number of wildfires have raged for weeks and are decimating the Brazilian Amazon, the world's largest tropical rainforest whose protection scientists say is critical to the fight against climate change.
The blazes have nearly doubled this year compared with the same period in 2018, according to Brazilian officials, prompting a global outcry.
Former Brazilian environment minister and presidential candidate Marina Silva on Thursday called wildfires raging in the Amazon rainforest a "crime against humanity" and blamed current policies for fueling the blazes.
As international criticism over the wildfires raging through the Amazon grew, Brazilian President Jair Bolsonaro admitted farmers could be illegally setting the rainforest ablaze but told foreign powers not to interfere.
Ireland said it will try to block a trade deal between the EU and South American bloc over the Amazon's rainforest destruction.
French President Emmanuel Macron and United Nations Secretary-General Antonio Guterres both took to Twitter to express concern about the fires that have reached a record number this year, devastating vast swathes of forest considered a vital bulwark against climate change.
Macron said the leaders of the Group of 7 nations should hold urgent discussions about them at their summit in France this weekend. The French president tweeted "Our house is burning," attaching a photograph of the Amazon AFP believes to be at least 16 years old.
Accusing Macron of 'colonialist mentality'
Bolsonaro responded angrily to what he regarded as meddling.
"These countries that send money here, they don't send it out of charity. ... They send it with the aim of interfering with our sovereignty," he said in a Facebook Live broadcast.
"The French president's suggestion that Amazon issues be discussed at the G-7 without participation by the countries in the region evokes a colonialist mentality that is out of place in the 21st century," Bolsonaro wrote on Twitter.
But earlier on Thursday, he said that Brazil alone lacked the resources to control the fires.
"The Amazon is bigger than Europe, how will you fight criminal fires in such an area?" he asked reporters as he left the presidential residence. "We do not have the resources for that."
Michael Fox reports.
Brazil's National Institute for Space Research, a federal agency monitoring deforestation and wildfires, said the country has seen a record number of wildfires this year, an 84 percent increase compared to the same period last year. The states that have been most affected by fires this year are Mato Grosso, Para and Amazonas, all in the Amazon region.
"The whole world is watching a situation that is out of control in terms of deforestation and fires in Brazil's Amazon," Silva told a conference in Bogota.
She and other environmentalists have blamed the Amazon's plight on cuts to environmental protections under the right-wing Bolsonaro, who took office in January riding a wave of populist support for his anti-corruption campaign.
"It's a situation I regard to be a crime against the homeland, a crime against humanity," Silva, a former senator, said.
"Throughout Brazil's history we have had difficult situations, but this is the first time we have a situation that was practically and officially fueled by the government," she added.
Although fires are a regular and natural occurrence during the dry season at this time of year, environmentalists blamed the sharp rise on farmers setting the forest alight to clear land for pasture.
Farmers may have had at least tacit encouragement from the firebrand right-wing president. Bolsonaro has repeatedly said he believes Brazil should open the Amazon up to business interests, to allow mining, agricultural and logging companies to exploit its natural resources.
On Wednesday, he blamed non-governmental organisations for setting the fires, without providing evidence. He appeared to row back on Thursday, when he said for the first time that farmers could be behind the fires.
Journalist Sam Cowie has more.
Ad for 'Fire Day'
Federal prosecutors in Brazil said they were investigating a spike in deforestation and wildfires raging in the Amazon state of Para to determine whether there has been reduced monitoring and enforcement of environmental protections.
Prosecutors said they would look into an ad that they said was published in a local newspaper encouraging farmers to participate in a "Fire Day," in which they would burn large areas of the forest "to show Bolsonaro their willingness to work."
Colombia, home to part of the northern Amazon, on Thursday offered its support in the fight to protect the forest.
"Colombian authorities are already working to contain the propagation of these fires toward Colombian territory and we are willing to collaborate with our neighbours in this common cause," the Foreign Ministry said in a statement.
Brazil is facing growing international criticism over its handling of the Amazon, 60 percent of which lies in the country.
Ireland will try to block a free trade deal between the EU and Mercosur bloc unless Brazil takes action to protect the Amazon rainforest, Irish Prime Minister Leo Vardakar was quoted as saying on Friday.
Irish Independent reported that Varadkar was very concerned at the record levels of rainforest destruction.
"There is no way that Ireland will vote for the EU-Mercosur free trade agreement if Brazil does not honour its environmental commitments," he said.
Earlier this month, Norway and Germany suspended funding for projects to curb deforestation in Brazil after becoming alarmed by changes to the way projects were selected under Bolsonaro.
At the time, when asked about the loss of German funding, Bolsonaro said, "Brazil does not need that."
Others were less sanguine.
Brazil's lower house speaker, Rodrigo Maia, said on Twitter he would create "an external committee" to monitor the burning of the rainforest, and he vowed to form a group "to evaluate the situation and propose solutions to the government."
The Bishops Conference for Latin America expressed concern about the "tragedy," and on Thursday called on countries to take immediate action to protect the rainforest and nearby communities.
"We urge the governments of the Amazon countries, especially Brazil and Bolivia, the United Nations and the international community to take serious measures to save the world's lungs," it said.
Wildfires are also raging in Bolivia, where officials estimate that an area the size of the US state of Delaware has burned in recent days.
Amnesty blames Brazil government
Amnesty International said Brazilian government failures are responsible for fires raging in the Amazon rainforest.
The comment by the rights group on Thursday came before Bolsonaro backtracked on his suggestion that some non-governmental groups could be setting the blazes in retaliation for losing state funds under his administration.
Kumi Naidoo, secretary-general of London-based Amnesty International, said the group has documented illegal land invasions and arson attacks in the Amazon, including a region where many fires are raging.
The World Meteorological Organization said this week that satellite images show smoke from Amazon fires is reaching the Atlantic coast and Sao Paulo.