UN boss tells London on hottest day, we face two crises as climate starts to fundamentally change

UN Secretary-General António Guterres has warned the world is facing a “tale of two crises” as climate breakdown and fossil fuel dependence collide.

Speaking at London Climate Action Week, Guterres said the climate crisis was pushing the world towards higher temperatures and dangerous tipping points, while the latest energy shock had again exposed the risk of economies built on oil and gas. Ironically he was delivering the talk on the hottest day of the year.

He said: “On the surface, this crisis may seem separate, but they share the same destructive origin. Fossil fuels. And they demand the same answer. A fast, fair transition to clean energy.”

Guterres said the world had just lived through the 11 hottest years ever recorded and warned London was “not just calling” but “cooking”, as temperatures climbed across the UK.

He said climate disasters were becoming more frequent, more destructive and more expensive, with the world now facing the risk of overshooting the 1.5°C target agreed in Paris.

Guterres warned every fraction of a degree mattered because higher temperatures increased the risk of irreversible tipping points, including coral reef collapse, faster ice loss in Greenland and west Antarctica, major sea level rise and parts of the Amazon shifting towards savanna-like conditions.

He said: “The Earth’s tipping points are like objects in car mirrors. They are far closer than they appear.”

The UN chief also linked current energy market turmoil to fossil fuel dependence, saying conflict in the Middle East had “unleashed the mother of all energy shocks”.

He said the crisis showed the limits of an old development model “powered by fossil fuels”, where one conflict or chokepoint can send prices soaring and leave poorer nations facing energy, food and development shocks.

But Guterres argued this crisis was different from previous energy shocks because clean alternatives are now cheaper and ready to scale.

He said solar costs had fallen by almost 90% since 2010, onshore wind by more than 70% and battery storage by 95%.

“There are no embargoes on sunlight and no blockades on the wind.”

His message was that energy security can no longer be built on fossil fuel dependence.

Guterres said renewables had become the cornerstone of true energy security and electrifying transport, buildings and industry was one of the fastest ways to cut emissions and reduce exposure to imported fuels.

He also launched a major push on methane, saying it was responsible for around one third of global warming and around 80 times more powerful than carbon dioxide over a shorter period.

He said the fossil fuel industry must act first because many of the fastest methane cuts can be made in coal, oil and gas.

The International Energy Agency has found around 70% of oil and gas methane emissions can be eliminated using existing technology, much of it at low or no net cost.

Guterres said: “Voluntary action is no longer enough.”

He called for a new global standard of near-zero methane emissions across the oil and gas value chain.

The speech also put AI data centres firmly into the climate and energy debate.

Guterres said artificial intelligence could help solve major problems but warned the technology was “hungry for land, water and power”.

By 2030, he said data centres could use more power than all but five countries and enough water to meet the basic needs of 1.3 billion people in sub-Saharan Africa for a year.

He announced an AI Environmental Transparency Initiative and called on major AI companies to publicly disclose the carbon, water and land footprints of their systems.

He said: “No more hidden costs, no more shifting the burden onto those least able to bear it.

“If AI is to help build a better future, it must be honest about what it costs us now.”

Secretary Guterres said the energy transition was no longer in question but warned it could be managed, or chaotic, fair or unequal. He concluded he would convene leaders in September ahead of COP31 in Turkey to drive progress on a just transition away from fossil fuels.