LONDON — The U.N.'s 25th annual international COP (Conference of the Parties) conference wrapped up Sunday — two days later than scheduled — with the world’s major polluters resisting calls to ramp up their efforts to keep global warming at bay.

The negotiators came to a compromise agreement that will see new carbon-cutting plans ready to be negotiated at next year's talks in Glasgow, Scotland, in November next year.

But the meeting put off the discussion of key issues like the regulation of global carbon markets until then, despite protests from smaller island nations, who were opposed the likes of China, Brazil and India.

“After 25 years I would be inclined to say the future of international cooperation on climate change is not looking good, but it’s not clear what the alternative would be,” said Richard Klein, senior research fellow at the Stockholm Environment Institute, who was in Madrid for the talks.

Activists protest outside of the COP25 climate talks congress in Madrid, Spain, Saturday, Dec. 14, 2019. The United Nations Secretary-General has warned that failure to tackle global warming could result in economic disaster. Manu Fernandez / AP

The talks were aimed at finalizing guidelines for implementing the 2015 Paris Agreement, which called for measures to prevent global temperatures from rising more than 3.6 degrees Fahrenheit and mitigate the consequences of climate change.

COP summits are important opportunities for smaller countries — some of whom are already experiencing the effects of climate change — to come together with larger, more industrialized countries, according to experts. Many of these smaller nations had hoped to win guarantees of financial aid to cope with climate change.

In the end, the conference declaration called for the “urgent need” to cut planet-heating greenhouse gases in line with the goals of the landmark 2015 Paris climate accord.

“The international community lost an important opportunity to show increased ambition on mitigation, adaptation and finance to tackle the climate crisis,” tweeted U.N. Secretary General António Guterres on Sunday, adding that he was “disappointed” with the result.

Scientists are now warning that these differences between countries could lead to even more inertia for next year’s crucial talks in Glasgow.

“What I am concerned about is that we are moving to a similar dynamic that we did before Copenhagen in that countries don’t trust each other anymore,” said Klein.

Swedish climate activist Greta Thunberg. Cristina Quicler / AFP - Getty Images

“Paris was a shared moment, there was a sense of urgency and the belief that collectively we could do something about this incredible problem. That sense of shared urgency seems to be going by the wayside,” he added.

Last month, President Donald Trump formally triggered the U.S.’s withdrawal from the 2015 accord, a process that will be completed a day after the next presidential election.

It means that the U.S., the second biggest emitter of greenhouse gases after China, will be excluded from many of the negotiations at next November's climate talks in Glasgow.

The lack of action at the summit comes as scientists and protesters step up their warnings on the urgency to take action. Around the world, groups this year have staged mass rallies demanding leaders take what they call the “climate emergency” seriously.

“The problem with climate change is that if you are late you will be punished for that. You can’t change the dynamics overnight,” said Elmar Kriegler, a senior scientist at the Potsdam Institute for Climate Impact Research.

Earlier at the summit, influential climate change activist Greta Thunberg denounced the pledges of wealthy countries and businesses to curb climate change as hollow and deceptive. She called them "clever accounting and creative PR" in a speech before world leaders at meeting.