France and Ireland say they will not ratify a huge trade deal with South American nations unless Brazil does more to fight fires in the Amazon.
French leader Emmanuel Macron said President Jair Bolsonaro had lied to him about his stance on climate change.
There are currently a record number of fires in the Amazon rainforest – a major source of oxygen for the world.
Environmental groups say the fires are linked to Mr Bolsonaro’s policies, which he denies.
European leaders have also expressed dismay over the fires, with UK Prime Minister Boris Johnson saying he is “deeply concerned” about “the impact of the tragic loss of these precious habitats”.
German Chancellor Angela Merkel has called the fire an “acute emergency… shocking and threatening not only for Brazil and the other affected countries, but also for the whole world”.
Mr Bolsonaro said on Friday that he was considering options for fighting the fires, including deploying the military.
However, he has also accused Mr Macron of meddling for “political gain”, and previously said calls to discuss the fires at this weekend’s G7 summit in Biarritz, France – which Brazil is not participating in – showed “a misplaced colonialist mindset”.
How significant is the trade deal?
It took 20 years of negotiations to strike the agreement with the South American bloc, consisting of Argentina, Brazil, Uruguay and Paraguay.
It would cut or remove trade tariffs on both sides, giving EU firms that make industrial products and cars access to Mercosur, and helping Mercosur countries export farm products, including beef, sugar, and poultry, to the EU.
But Mr Macron, and Ireland’s Prime Minister Leo Varadkar, now say they will not ratify the EU-Mercosur trade deal unless Brazil shows a commitment to protecting the environment.
“Given the attitude of Brazil over the last weeks, the president can only conclude that President Bolsonaro lied to him at the Osaka (G20) summit (in June),” and did not intend to meet climate change obligations, a French presidential official said on Friday.
Why are people so worried about the fires?
The largest rainforest in the world, the Amazon is a vital carbon store that slows down the pace of global warming.
It is known as the “lungs of the world” and is home to about three million species of plants and animals, and one million indigenous people.
UN Secretary-General Antonio Guterres tweeted on Thursday: “In the midst of the global climate crisis, we cannot afford more damage to a major source of oxygen and biodiversity. The Amazon must be protected.”