Almost every country in the world has signed up to the “historic” agreement to cut greenhouse gas emissions and slow global warming.
Delegates from around the world cheered and hugged one another after it was announced that 195 countries had ratified the Paris agreement after intense negotiations.
French foreign minister Laurent Fabius brought the gavel down on the deal more than 24 hours after the official end of the fortnight-long conference in the French capital, following days and nights of shuttle diplomacy and wrangling between countries.
There were tears and a standing ovation in the conference hall, as well as cheers, clapping and shouts in the media room and among environmental campaigners in other rooms.
The deal is the world’s first comprehensive climate agreement, which will see all countries taking action to tackle the problem. Climate change talks in Copenhagen in 2009 stalled after countries failed to reach an agreement.
The text of the Paris agreement commits to keeping global temperature rises “well below” 2C, and “pursue efforts to limit the temperature increase to 1.5C”.
Some experts believe the worst impact of climate change will be felt if global warming reaches 2c.
The goal on emissions reductions has changed from “greenhouse gas emissions neutrality” and now calls for gases to peak as soon as possible, with rapid reductions “in accordance with best available science”, and “a balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of this century”.
The language of the draft is weaker than some previous options which had specific figures for emissions cuts.
Countries are being asked to submit climate action plans for emissions, with reviews and updates every five years. This could be crucial, as plans already submitted by countries up to 2030 are not enough to put the world on a path to limiting temperature rises to 2C.
The text also ensures there will be finance for less developed countries to grow their economies using low-carbon industry, subsidised by $100bn from developed countries.
Reacting to the news, US President Barack Obama tweeted: “This is huge: Almost every country in the world just signed on to the #ParisAgreement on climate change – thanks to American leadership.”
Prime Minister David Cameron said: “In striking this deal, the nations of the world have shown what unity, ambition and perseverance can do.
“Britain is already leading the way in work to cut emissions and help less developed countries cut theirs – and this global deal now means that the whole world has signed to play its part in halting climate change. It’s a moment to remember and a huge step forward in helping to secure the future of our planet.”
Energy and Climate Change Secretary Amber Rudd, who was part of the EU ministerial team negotiating the deal, said: “We have witnessed an important step forward, with an unprecedented number of countries agreeing to a deal to limit global temperature rises and avoid the worst impacts of climate change.
“This is vital for our long-term economic and global security. This deal will ensure all countries are held to account for their climate commitments and gives a clear signal to business to invest in the low carbon transition.”
Earlier, French president Francois Hollande told delegates: “This text will, if you should so decide, be the first universal agreement in history on climate change.
“You will make a choice for your country, for your continent, but also a choice for the world. It will be a major leap for mankind.”
He added: “History is here.”
Michael Jacobs, senior adviser for the New Climate Economy project, and former adviser to Gordon Brown, said: “Historians will see this as the turning point: the moment when the world started shifting decisively away from fossil fuels and towards clean and safe energy systems.
“Remarkably this effectively signals the end of the fossil fuel era. This is unquestionably a great success. But the work really starts now. These commitments now need to turn into policy, and policy into investment.”
Kumi Naidoo, executive director of Greenpeace International, said: “The wheel of climate action turns slowly, but in Paris it has turned. This deal puts the fossil fuel industry on the wrong side of history.”
Prof Sir Brian Hoskins, chairman of the Grantham Institute, Imperial College London, said: “The Paris agreement is the culmination of more than 20 years of negotiation.
“With it the countries of the world have recognised that they all have to work together to tackle the shared problem of dangerous climate change caused by human activities.
“We are now looking towards the post- fossil fuel era that will give new opportunities for technological, economic and social development that is truly sustainable.”