“Humanity is waging war on nature. This is suicidal,” the UN secretary-general António Guterres declared on Wednesday, in an angry speech that implicitly criticised world leaders and the fossil-fuel industry for insufficient action against climate change.

He pointed to the growing number of “apocalyptic fires and floods, cyclones and hurricanes” as examples of climate-related man-made destruction.

“Nature always strikes back — and it is already doing so with growing force and fury. Biodiversity is collapsing. One million species are at risk of extinction. Ecosystems are disappearing before our eyes… Human activities are at the root of our descent toward chaos,” he said.

“This is an epic policy test. But ultimately this is a moral test. The trillions of dollars needed for Covid recovery is money that we are borrowing from future generations. Every last penny. We cannot use those resources to lock in policies that burden them with a mountain of debt on a broken planet.”

He added: “It is time to flick the ‘green switch’. We have a chance to not simply reset the world economy but to transform it.

“Making peace with nature is the defining task of the 21st century. It must be the top, top priority for everyone, everywhere.”

His speech at Columbia University in New York came on the same day as the UN and partner agencies released a report condemning G20 governments for supporting the fossil-fuel sector with $233bn of post-Covid economic recovery funding — compared to the $146bn for renewable energy and other low-carbon solutions.

“Policymakers must reverse this trend to meet climate goals,” said the Production Gap study.

The report said that the world must reduce production of coal, oil and gas by 6% per year until 2030 to keep climate change under the 1.5C target stipulated in the Paris Agreement. Yet production is increasing by 2% annually — backed by loans that future generations will have to repay.

Unlike Guterres’ speech, this report was not afraid to the point the finger at individual governments, citing the worst offenders as the US, the UK, Germany, India, Turkey, Canada, Russia, Indonesia and South Korea.

“The pandemic-driven plunge in oil prices this year has once again demonstrated the vulnerability of many fossil-fuel-dependent regions and communities,” said Ivetta Gerasimchuk of the International Institute for Sustainable Development, who was a lead author of the report. “Alas, in 2020 we saw many governments doubling down on fossil fuels. Instead of governments letting these fossil-fuel projects die, they resurrect them from death – it’s kind of zombie energy.”

Another report released on Wednesday, by the World Meteorological Organisation, said that 2020 would be the third-hottest year on record — despite the temporary reduction in greenhouse gas emissions growth due to the pandemic.

Yet despite the doom and gloom, both Guterres and the Production Gap study, said the situation could still be turned around.

The UN boss pointed to the net-zero emissions targets set by China, the EU, Canada, Japan and others as reason for hope, but warned that these pledges needed to be translated into concrete action.

“We need all governments to translate these pledges into policies, plans and targets with specific timelines. This will provide certainty and confidence for businesses and the financial sector to invest for net zero.”

He added: “The central objective of the United Nations for 2021 is to build a truly Global Coalition for Carbon Neutrality. I firmly believe that 2021 can be a new kind of leap year — the year of a quantum leap towards carbon neutrality.

“Every country, city, financial institution and company should adopt plans for transitioning to net zero emissions by 2050 — and I encourage the main emitters to lead the way in taking decisive action now to get on the right path and to achieve this vision, which means cutting global emissions by 45 percent by 2030 compared with 2010 levels.”

He called on governments to put a price on carbon, halt fossil-fuel investment, phase out fossil-fuel subsidies, stop building coal-fired power plants and shift from taxing incomes to taxing pollution.

The Production Gap report said policymakers “can support a managed, just, and equitable wind-down of fossil fuel production through six areas of action: sustainable stimulus and recovery packages, increased support for just and equitable transitions, reduced support for fossil fuels, restrictions on production, improved transparency, and global cooperation”.