GLASGOW—Organizers of climate talks released what they described as a near-final draft of a deal that they hope will survive a day of haggling and emerge as a meaningful commitment by more than 190 governments to step up the fight against climate change.

Even before talks at the United Nations summit, called COP26, started two weeks ago, governments’ climate plans fell short of what scientists say is needed to stave off the worst effects of an increase in global temperatures. Negotiators, in an attempt to keep that goal within...

GLASGOW—Organizers of climate talks released what they described as a near-final draft of a deal that they hope will survive a day of haggling and emerge as a meaningful commitment by more than 190 governments to step up the fight against climate change.

Even before talks at the United Nations summit, called COP26, started two weeks ago, governments’ climate plans fell short of what scientists say is needed to stave off the worst effects of an increase in global temperatures. Negotiators, in an attempt to keep that goal within reach in the near future, are trying to convince delegates to sign onto a pledge to revisit those commitments next year.

That could then result, they hope, in additional cuts scientists say are still necessary to keep global warming well below 2 degrees Celsius, and closer to 1.5 degrees, above preindustrial-era temperatures. Those temperature goals were set at a similar summit in Paris in 2015. The U.N. has said plans submitted before the Glasgow summit put the world on track for 2.7 degrees of warming.

“This is the shape of the outcome,” said one of the negotiators of the draft on Saturday morning. The text set up a deal that would keep “1.5 degrees Celsius within reach,” this negotiator said.

Delegates have blown past their deadline of wrapping up talks by Friday. Some differences between various blocs were ironed out in all-night talks, according to negotiators and based on the latest draft text.

U.K. negotiator Archie Young, standing, speaks to a delegate from India on Saturday.

Photo: PHIL NOBLE/REUTERS

In addition to the summit’s core aim of getting commitments for deeper emissions cuts, negotiators have been at loggerheads over a host of other issues that various blocs believed could turn a U.N. deal here into a meaningful road map to fighting climate change.

They include an effort to boost funding by rich countries to poorer ones to help them adapt to the effects of climate change. Negotiators are also trying to nail down a framework for cross-border trade of carbon credits and provide rules around how countries report emissions and other data.

Conference host the U.K., along with many other countries, are trying to insert language about discouraging the use of coal and other fossil fuels, which are heavy greenhouse-gas-emitting energy sources. The language doesn’t come with any enforcement teeth or a concrete deadline, but backers hope it will take on symbolic significance if it makes it into any final deal.

The main dispute between developed and developing countries has centered around climate finance, as poor countries seek more money from rich countries to help them adopt renewable energy and protect themselves from the effects of climate change. Negotiators are proposing a doubling of the share of funding meant to help countries adapt to climate change. That is part of a broader debate over a $100-billion-a-year commitment that rich countries agreed to in 2015. Developed nations haven’t yet fully fulfilled that pledge, and poorer countries are skeptical that their push for even more funding has a chance without the initial pledge being met.

Climate talks were scheduled to wrap up on Friday but continued into the weekend.

Photo: robert perry/Shutterstock

Negotiators are also at odds over so-called loss-and-damage provisions, meant to provide funds to countries where the effects of climate change are determined to already be so severe that adaptation alone won’t help. Countries like Tuvalu and the Maldives say sea-level rises have already created an existential crisis. Such payments would essentially act as compensation by richer nations.

Saturday’s draft of the “cover decision,” or headline agreement, for the first time mentions the issue and commits parties to a dialogue on how to address this. Negotiators from developing nations have been pushing for more concrete measures, but the U.S. and European Union have so far remained reluctant to set up a dedicated fund in part over legal concerns, according to people familiar with the talks.

The draft calls for countries to update their emissions targets for 2030 by the end of next year. But even that language—which may not make the final deal—has caveats: the exercise, for instance, is largely voluntary.

Many governments who have recently submitted their national emissions plans now need time to pass them into law and implement them. They currently have until 2025 to update those plans, according to the Paris accord of 2015.

The U.S. and China, meanwhile, have been working through disagreements on how much detail countries need to provide on their emissions and financial support data, according to one negotiator. Earlier in the week the world’s two biggest emitters and economies promised to step up joint actions to fight climate change in the coming decades. That injected talks with new momentum, negotiators said, by signaling to other parties that both sides were willing to set aside differences for a deal at COP26.

A deal on establishing the foundations of an international carbon-trading system is close to the finishing line, according to negotiators. Talks overnight helped bridge some gaps, with one negotiator saying the outlook for an agreement on Saturday was “overall promising.”

Diplomatic haggling is expected to continue throughout the day to iron out a legal text.

Write to Sha Hua at sha.hua@wsj.com, Sarah McFarlane at sarah.mcfarlane@wsj.com and Max Colchester at max.colchester@wsj.com