Negotiators are attempting to agree a deal in the Spanish capital that would see countries commit to make new climate pledges by the end of 2020.
But serious disagreements have emerged over how much carbon-cutting the major emitters should undertake.
The talks have also become bogged down in rows over key technical issues.
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Negotiators arrived in Madrid two weeks ago with the words of the UN secretary general ringing in their ears - António Guterres told delegates that "the point of no return is no longer over the horizon".
Despite his pleas, the conference has become enmeshed in deep, technical arguments about a number of issues including the role of carbon markets and the financing of loss and damage caused by rising temperatures.
The key question of raising ambition has also been to the forefront of the discussions.
Responding to the messages from science and from school strikers, the countries running this COP are keen to have a final decision here that would see countries put new, ambitious plans to cut carbon on the table.
According to the UN, 84 countries have promised to enhance their national plans by the end of next year. Some 73 have said they will set a long-term target of net zero by the middle of the century.
In a rare move, negotiators from the Alliance of Small Island States (AOSIS) pointed the finger of blame at countries including Australia, the United States, Canada, Russia, India, China and Brazil.
They had failed to submit revised plans that would help the world keep the rise in global temperatures under 1.5C this century.
As well as naming names, AOSIS members were angry at the pressure being put on the island nations to compromise on key questions.
"We are appalled at the state of negotiations - at this stage we are being cornered, we fear having to concede on too many issues that would undermine the very integrity of the Paris agreement," said Carlos Fuller, AOSIS chief negotiator.
"What's before us is a level of compromise so profound that it underscores a lack of ambition, seriousness about the climate emergency and the urgent need to secure the fate of our islands."
Reinforcing the sense of division, India, supported by China, Saudi Arabia and Brazil, is taking a hard line on the promises made by richer countries in previous agreements before the Paris pact was signed in 2015.
They are insisting that the pledges to cut carbon in the years up to 2020 be examined and if the countries haven't met their targets, these should be carried over to the post-2020 era.
Signed in 2015, the Paris climate pact saw every country, India included, sign up to take actions.
This was a key concession to the richer nations who insisted that the deal would only work if everyone pledged to cut carbon, unlike previous agreements in which only the better off had to limit their CO2.
India now wants to see evidence that in the years up to 2020, the developed world has lived up to past promises.
"The Paris agreement talks about the leadership of the developed countries, it talks about the peaking of greenhouse gases earlier in these countries, so we need to see these things," said Ravi Shankar Prasad, India's chief negotiator.
"You have to honour what you agreed."
The developed world see the Indian stance as a tactic, where they are trying to go back to the way things were before Paris, with the richer countries doing the most of the heavy lifting while China, India and others do less.
Some politicians in attendance at this meeting believe there's too much self interest and not enough countries looking at the bigger picture.
"Frankly, I'm tired of hearing major emitters excuse inaction in cutting their own emissions on the basis they are 'just a fraction' of the world's total," said the prime minister of Fiji, Frank Bainimarama.
"The truth is, in a family of nearly 200 nations, collective efforts are key. We all must take responsibility for ourselves, and we all must play our part to achieve net zero.
"As I like to say, we're all in the same canoe. But currently, that canoe is taking on water with nearly 200 holes - and there are too few of us trying to patch them," Mr Bainimarama said.