The deal has taken 20 years to negotiate, but Brazil’s lack of environmental protection has sparked worldwide anger.

As wildfires rage through the Amazon, Irish Prime Minister Leo Varadkar and French President Emmanuel Macron have said they will vote against a trade deal between the European Union and South American trade bloc Mercosur unless Brazil takes action to protect the rainforest.

Varadkar said in a statement on Friday he was very concerned at the record levels of rainforest destruction, adding that the Irish government would closely monitor Brazil’s environmental actions in the two years until the Mercosur deal is ratified.

“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.

Macron, meanwhile, believes his Brazilian counterpart Jair Bolsonaro lied to him on Brazil’s stance on climate change, and France will now join Ireland in blocking the trade deal between the EU and South American nations.

“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],” a French presidential official said on Friday, as a public row flared between the two leaders over wildfires raging in the Amazon rainforest.

Brazil’s comments and policies over the past few weeks showed the right-wing Bolsonaro did not intend to respect obligations on climate change and also did not want to commit on concrete proposals to maintain biodiversity, said the official.

“Under these conditions, France will oppose the Mercosur (Free Trade Agreement with the EU) as it stands,” the French official added.

About 500 protesters, many from the Extinction Rebellion climate strike group, blocked the road outside Brazil’s embassy in London on Friday morning, incensed at Bolsonaro’s lack of environmental protections.

“When we destroy elements of biodiversity, we cut the threads that hold everything together,” Farnan Ellwood of the University of the West of England, told Al Jazeera. “Biodiversity is nature’s protection mechanism, its insurance policy.

“We need to stop using hardwood furniture, stop eating beef – because it’s the beef farming which is driving deforestation. The second thing is to recognise the world has changed – we simply cannot go back. But there is some good news; scientists are trying to rebuild the biodiversity. If we can put the fire out – literally and figuratively – and stop the decline, then we can try to restore some of these complex networks of biodiversity.”

Macron had tweeted on Thursday that fires burning in the Amazon amounted to an international crisis and should be discussed as a top priority when the G7 countries meet this weekend in France.

Bolsonaro then blasted Macron for having a “colonialist mentality”. German Chancellor Angela Merkel joined Macron’s call on Friday, and it looks likely to be a topic for discussion.

Vast tracts of the Amazon – often described as the lungs of the world – are currently ablaze in what is known as the burning season. Environmentalists have blamed deforestation for an increase in fires and accuse Bolsonaro of cutting protection of an area deemed crucial in combating climate change.

Varadkar said Bolsonaro’s effort to blame non-government environmental organisations for the fires was “Orwellian”.

Ireland and France will need other EU states to help form a blocking minority if it wants to kill the deal which was reached in June after 20 years of negotiations between the EU and the Mercosur countries – Brazil, Argentina, Uruguay and Paraguay.

But the Irish government is under pressure to defend its beef farmers, already suffering from Britain’s looming EU exit and low prices, by seeking to ensure Mercosur countries do not flood the market with cheaper beef.

Bolsonaro has rejected what he calls foreign interference in Brazil’s affairs.