Leaked documents show that the biggest producers of oil, coal and beef are lobbying scientists intensely to try to strip a landmark climate report of recommendations that threaten their interests.
Australia, Saudi Arabia and Japan are among the countries pressuring the Intergovernmental Panel on Climate Change (IPCC) to remove or weaken the conclusion that the world needs to phase out fossil fuels.
The documents have been obtained by Unearthed, Greenpeace's team of investigative journalists, and the BBC.
They show how Australia, for example, rejected the widely-accepted science that eliminating coal-fired power stations was one of the most important ways of reducing greenhouse gases.
Australia is the world's fifth largest coal producer.
Rather than phasing out fossil fuels, Saudi Arabia's approach involves relying on unproven technologies to remove carbon from the atmosphere after fuels are burned.
Brazil and Argentina have also reportedly made comments pressing the report's authors to delete messages about the climate benefits of undertaking a "plant-based" diet, despite a study in 2018 finding that moving to a meat-free diet could cut food land use, and reduce emissions by 49%.
The IPCC report is due to be published next year.
It said its processes are designed to guard against lobbying from all quarters and it only accepts changes if they are supported by science.
The leak comes ahead of the United Nations Climate Change Conference (COP26) which gets under way in Glasgow later this month.
Some 30,000 delegates, including world leaders, are due in the Scottish city for what is billed as a make-or-break summit to strengthen commitments to keep global warming below 2 degrees Celsius - preferably 1.5C.
Greenpeace Chief Scientist Dr Doug Parr said the organisation felt it was important to publish the documents to show other countries what they are dealing with ahead of the COP26 negotiations.
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Indian PM Modi to attend COP26 conference
India's Prime Minister Narendra Modi will attend the COP26 climate summit in Glasgow, it has emerged.
Mr Modi will join other world leaders including US President Joe Biden and British Prime Minister Boris Johnson at the talks, although the leaders of some major polluting countries are set to the skip the event.
Mr Johnson's spokesman welcomed confirmation of Mr Modi's attendance.
"We welcome that news, and all the world leaders, I think we're above 120 now confirmed.
"India play an important role in this and the prime minister has had a number of conversations with Modi on the importance of climate change, so we look forward to discussing it with him further."
Additional reporting PA