The hard truth is that we have failed to ensure we remain below 1.5 degrees.

Science now tells us that a temporary overshoot beyond the 1.5 limit — starting at the latest in the early 2030s — is inevitable. We need a paradigm shift to limit this overshoot’s magnitude and duration and quickly drive it down.

Even a temporary overshoot will have dramatic consequences. It could push ecosystems past irreversible tipping points, expose billions to unlivable conditions, and amplify threats to peace and security. Every fraction of a degree means more hunger, displacement, and loss — especially for those least responsible.

This is moral failure — and deadly negligence.

Yes, the newly submitted Nationally Determined Contributions (NDC) represent progress — but they still fall short of what is needed. Even if fully implemented, they would put us on a pathway well above 2 degrees of global warming.

Let us be clear: the 1.5°C limit is a red line for humanity. It must be kept within reach. And scientists also tell us that this is still possible. If we act now, at speed and scale, we can make the overshoot as small, as short, and as safe as possible — and bring temperatures back below 1.5°C before century’s end. Small — by peaking global emissions immediately; cutting them deeply this decade, accelerating the phase out of fossil fuels, slashing methane, and safeguarding forests and oceans — nature’s carbon sinks. Short — by reaching global net zero by 2050 and moving swiftly to sustained net-negative emissions afterwards. Safe — by drastically increasing investments in adaptation and resilience, and delivering Early Warnings for All by 2027.

The United Nations will not give up on the 1.5 degrees goal. Because another truth is evident: we have never been better equipped to fight back.

A clean energy revolution has taken hold. Solar and wind are now the cheapest sources of power — and the fastest growing sources of electricity in history. Last year, almost all new power capacity came from renewables. The clean-energy economy is creating jobs and driving development. It is reshaping geopolitics — delivering energy security and price stability. And it is connecting millions to clean and affordable energy for the first time.

The economics have shifted. In 2024, investors poured 2 trillion US dollars into clean energy — 800 billion more than fossil fuels. Clean energy is winning on price, performance, and potential — offering the solutions to transform our economies and protect our populations.

What’s still missing is political courage. Fossil fuels still command vast subsidies — taxpayers’ money. Too many corporations are making record profits from climate devastation — with billions spent on lobbying, deceiving the public and obstructing progress. Too many leaders remain captive to these entrenched interests. Too many countries are starved of the resources to adapt — and locked out of the clean energy transition. And too many people are losing hope that their leaders will act. We need to move faster — and move together. This COP must ignite a decade of acceleration and delivery.

First — countries must agree on a bold and credible response plan to close the NDC ambition gap to 1.5 degrees. Common But Differentiated Responsibilities must apply, but that should not be an excuse for any country not to assume its fair share. This means supercharging renewables, electrification, and energy efficiency; building modern grids and large-scale storage; halting and reversing deforestation by 2030; cutting methane emissions; and setting near-term, 1.5-aligned coal phase-out schedules.

I have consistently advocated against more coal plants or fossil fuel exploration and expansion. At COP 28 in Dubai, countries committed to transition away from fossil fuels. No more greenwashing. No loopholes. We must turn that commitment into action — while supporting low- and middle-income developing countries that are highly dependent on fossil fuels. We must also dismantle structural barriers and provide the conditions for developing countries to deliver and exceed their NDC commitments. Trade and investment policies must support climate ambition, not undermine it.

Second — we must demonstrate a clear and credible path to reaching the $1.3 trillion a year in climate finance for developing countries by 2035, as agreed at COP 29 in Baku. Developed countries must take the lead in mobilizing $300 billion annually — delivering affordable, predictable finance at the agreed scale. All providers must show they will contribute to meeting the 300 billion and 1.3 trillion milestones.

It’s no longer time for negotiations. It’s time for implementation, implementation and implementation. With independent tracking, faster disbursement, and terms that reflect climate vulnerability — including debt relief.

And third — developing countries must leave Belém equipped with a climate justice package that delivers equity, dignity, and opportunity. That means a concrete plan to close the adaptation finance gap:

Ensuring that developed countries honor their pledge to provide $40 billion adaptation finance by the end of this year;

And giving confidence that affordable adaptation finance will be scaled up beyond 2025 — and delivered swiftly to the communities on the frontlines.

It also means placing justice at the heart of the transition. With concrete measures to support developing countries to navigate it — protecting workers, empowering communities, and creating new opportunities; and significant contributions and simplified access to the Loss and Damage Fund.

A just transition also means Indigenous Peoples leading the way. Their knowledge and full participation light the path to a livable planet.

You can count on the United Nations. Through our Climate Promise, over a hundred developing countries received support in the preparation of their new NDC. I have directed the United Nations Development Program to build on this architecture and work across the system to support developing countries during the implementation plan.

The challenge is immense. But the choices are clear. No one can bargain with physics. But we can choose to lead — or be led to ruin. Choose to make Belém the turning point. Stand with science. Stand for justice. Stand for future generations.

(Excerpts of United Nations Secretary-General António Guterres ‘s remarks at the Plenary of Leaders of the Belém Climate Summit in Belem, Brazil on 6 November 2025.)