The coverage on this live blog is now over.

World leaders met in Glasgow, U.K., on Monday for the first day of the highly anticipated COP26 climate summit.

Delegates were asked to accelerate action on climate change and commit to more ambitious cuts in their countries' emissions, all in an effort to limit global temperature rises.

Here are some of the biggest developments Monday:

• COP26 a 'minute to midnight moment,' U.K.'s Johnson says{

  04:58 am: COP26 a ‘minute to midnight moment,’ U.K.’s Johnson says

  

  Speaking to the BBC, British Prime Minister Boris Johnson said COP26 marked a "one minute to midnight moment."

  "The clock is ticking – we have to get everybody to do more and make further commitments," he said.

  Those commitments need to include actions like moving away from the use of fossil fuels, using electric vehicles and planting millions, if not a trillion, trees around the world, he added.

  "Above all, [we need to work out] how we're going to get the whole of the developing world to buy into all of this," Johnson said.

  — Chloe Taylor

  =null}
• G-20 must lead efforts to reduce emissions, UN's Guterres says{

  09:11 am: G-20 must lead efforts to reduce emissions, UN’s Guterres says

  

  The U.N.'s Guterres warns that as COP26 begins, the world is still heading for climate disaster.

  "Recent carbon announcements might give the impression that we are on track to turn things around," he says. "This is an illusion."

  He adds that humanity "faces a moment of truth" and is "fast approaching a tipping point."

  "The science is clear, we know what to do," Guterres says. "We must keep the goal of 1.5 degrees Celsius alive. This requires greater ambition on mitigation and immediate concrete action to reduce global emissions by 45% by 2030. G-20 countries have a particular responsibility, as they represent around 80% of emissions … Developed countries must lead the effort."

  — Chloe Taylor

  =null}
• Prince Charles: We must marshal strength of the private sector{

  09:19 am: Prince Charles: We must marshal strength of the private sector

  

  Prince Charles, addressing delegates at the summit, says the Covid-19 pandemic has demonstrated just how devastating a global cross-border threat can be.

  "Climate change and biodiversity loss are no different — in fact they pose an even greater existential threat, to the extent that we have to put ourselves on what might be called a war-like footing," he says.

  He calls for a radical transformation of our fossil fuel-based economy to one that is genuinely renewable and sustainable.

  "My plea today is for countries to come together to create the environment that enables every sector of industry to take the action required. We know this will take trillions, not billions, of dollars," Prince Charles says. "We need a vast military-style campaign to marshal the strength of the private sector. With trillions at its disposal — far beyond global GDP and beyond the governments of the world's leaders, it offers the only real prospect of achieving fundamental economic transition."

  — Chloe Taylor

  =null}
• Biden: 'None of us can escape the worst that's yet to come if we fail to seize this moment'{

  11:00 am: Biden: 'None of us can escape the worst that's yet to come if we fail to seize this moment'

  U.S. President Joe Biden warned in his COP26 speech on Monday that "in an age where this pandemic has made so painfully clear that no nation can wall itself off from borderless threats, we know that none of us can escape the worst that's yet to come if we fail to seize this moment."

  Biden added that "within the growing catastrophe I believe there's an incredible opportunity, not just for the United States but for all of us."

  He said that there was an opportunity to build an "equitable, clean energy future" that could create "millions of good paying jobs in the process" around the world.

  Biden added that creating an environment that raised the standard of living around the world was both a "moral" and "economic imperative."

  — Vicky McKeever

  =null}

11:00 am: Biden: 'None of us can escape the worst that's yet to come if we fail to seize this moment'

U.S. President Joe Biden warned in his COP26 speech on Monday that "in an age where this pandemic has made so painfully clear that no nation can wall itself off from borderless threats, we know that none of us can escape the worst that's yet to come if we fail to seize this moment."

Biden added that "within the growing catastrophe I believe there's an incredible opportunity, not just for the United States but for all of us."

He said that there was an opportunity to build an "equitable, clean energy future" that could create "millions of good paying jobs in the process" around the world.

Biden added that creating an environment that raised the standard of living around the world was both a "moral" and "economic imperative."

— Vicky McKeever

10:56 am: President Biden says COP26 must be the 'kick off of a decade of ambition'

President Joe Biden told delegates at the COP26 summit on Monday that there is only a "brief window left before us to raise our ambitions, and to raise to meet the task that's rapidly narrowing."

He said this would be the "decisive decade" in which to prove that the goal of limiting global warming to just 1.5 degrees Celsius could be met.

"That's what COP26 is all about, Glasgow must be the kick off of a decade of ambition and innovation to preserve our shared future," Biden said.

— Vicky McKeever

10:11 am: COP26 must be a quantum leap in fight against climate change, Italy’s Draghi says

Italian Prime Minister Mario Draghi says there are tens of trillions of dollars available in the private sector.

"But now we've got to use them," he tells COP26 attendees. "Now we have to find an intelligent way to spend them and spend them quickly. We need, first and foremost, all multilateral development banks – especially the World Bank – to co-share with the private sector risks that the private sector alone cannot bear."

"Money is not a concern if we want to use it well," Draghi adds. "This COP26 must be the start of a new momentum, a quantum leap in our fight against climate change."

— Chloe Taylor

10:07 am: 2 million Kenyans facing climate-related starvation, activist says

"I need to tell you what is happening in my home country," Elizabeth Wathuti, a climate activist from Kenya, said at COP26 on Monday. "Right now, as you sit comfortably in this conference center Glasgow, over 2 million of my fellow Kenyans are facing climate-related starvation."

"By 2025, half of the world's population will be facing water scarcity and by the time I'm 50, the climate crisis will have displaced 86 million people in sub-Saharan Africa alone," Wathuti, aged 26, said.

Wathuti led a moment's silence for the billions of people who were not present in Glasgow, whose stories were not being heard and whose suffering was not being felt. "Please open your hearts. If you allow yourself to feel it, the heartbreak and the injustice is hard to bear," she said.

— Sam Meredith

10:03 am: David Attenborough: Is this how our story is due to end?

Naturalist David Attenborough says the burning of fossil fuels and humanity's destruction of nature are releasing carbon into the atmosphere at an unprecedented pace and scale.  

"We are already in trouble," he warns. "The civility we all depend on is breaking."

"Is this how our story is due to end?" Attenborough adds. "A tale of the smartest species doomed by that all too human characteristic of failing to see the bigger picture in pursuit of short-term goals. If working apart we are force powerful enough to destabilize our planet, surely working together we are powerful enough to save it."

— Chloe Taylor

09:47 am: We need to limit warming to 1.5 degrees to survive, Barbados prime minister says

"For those who have eyes to see, for those who have ears to listen and for those who have a heart to feel, 1.5 is what we need to survive," Mia Mottley, prime minister of Barbados, said on Monday.

She added that 2 degrees Celsius of heating "is a death sentence for the people of Antigua and Barbuda, for the people of the Maldives, for the people of the Dominica and Fiji, for the people of Kenya and Mozambique, and yes, for the people of Samoa and Barbados.

"We do not want that dreaded death sentence and we have come here today to say: Try harder."

— Sam Meredith

09:33 am: Glacial lake outburst floods threaten from above

In and around the world's highest mountains, glacial lake outburst floods pose a worsening threat to an increasing number of people.

Glaciers are extremely sensitive to climate change, and as hot air melts ice and pushes glaciers into retreat, huge new lakes are appearing in high, often precarious pockets within mountain ranges. Many are poised to burst their banks.

Read our immersive article to find out more.

— Sam Meredith

09:19 am: Prince Charles: We must marshal strength of the private sector

Prince Charles, addressing delegates at the summit, says the Covid-19 pandemic has demonstrated just how devastating a global cross-border threat can be.

"Climate change and biodiversity loss are no different — in fact they pose an even greater existential threat, to the extent that we have to put ourselves on what might be called a war-like footing," he says.

He calls for a radical transformation of our fossil fuel-based economy to one that is genuinely renewable and sustainable.

"My plea today is for countries to come together to create the environment that enables every sector of industry to take the action required. We know this will take trillions, not billions, of dollars," Prince Charles says. "We need a vast military-style campaign to marshal the strength of the private sector. With trillions at its disposal — far beyond global GDP and beyond the governments of the world's leaders, it offers the only real prospect of achieving fundamental economic transition."

— Chloe Taylor

09:11 am: G-20 must lead efforts to reduce emissions, UN’s Guterres says

The U.N.'s Guterres warns that as COP26 begins, the world is still heading for climate disaster.

"Recent carbon announcements might give the impression that we are on track to turn things around," he says. "This is an illusion."

He adds that humanity "faces a moment of truth" and is "fast approaching a tipping point."

"The science is clear, we know what to do," Guterres says. "We must keep the goal of 1.5 degrees Celsius alive. This requires greater ambition on mitigation and immediate concrete action to reduce global emissions by 45% by 2030. G-20 countries have a particular responsibility, as they represent around 80% of emissions … Developed countries must lead the effort."

— Chloe Taylor

09:01 am: UN’s Guterres: Humanity faces a stark choice

United Nations Secretary-General Antonio Guterres tells the summit the six years since the Paris Agreement was adopted have been the six hottest years on record.

"Our addiction to fossil fuels is pushing humanity to the brink," he says. "We face a stark choice: either we stop it, or it stops us. And it's time to say 'enough.'"

He adds that we are "killing ourselves with carbon" and "treating nature like a toilet."

— Chloe Taylor

08:46 am: World leaders must get real about climate change at COP26, UK’s Johnson says

Britain's Johnson warns that in a world where warming hits 4 degrees Celsius, whole cities — such as Miami, Alexandria and Shanghai — will be "lost beneath the waves."

"If we don't get serious about climate change today, it will be too late for our children to do so tomorrow," he tells the COP26 summit.

"The anger and impatience of the world will be uncontainable unless we make COP26 the moment when we get real about climate change. And we can get real on coal, cars, cash and trees. We have the technology to deactivate that ticking doomsday device."

— Chloe Taylor

08:39 am: UK leader Boris Johnson kicks off speeches

British Prime Minister Boris Johnson has taken to the stage at the COP26 opening ceremony to address delegates.

"This is not a movie — the doomsday device is real," he warns. "The longer we wait, the worse it gets … it's one minute to midnight on that doomsday clock and we need to act now."

— Chloe Taylor

08:21 am: G-20 not doing enough to protect climate, U.K. lawmaker says

Speaking to CNBC's Steve Sedgwick at COP26, the U.K.'s Shadow Business Secretary Ed Miliband said he was confident a deal would happen at the summit, but he questioned whether it would be sufficient.

"We've got to halve carbon emissions this decade… we're a long way off where we need to be," he said, adding that the summit needed to "turn up the heat" on world leaders.  

"No G-20 country is doing enough, everyone's got to step up," Miliband said.

— Chloe Taylor

07:20 am: White House advisor says China must meet climate responsibilities

U.S. National Security Advisor Jake Sullivan told reporters on Monday that China — the world's largest emitter of greenhouse gases — must do more to reduce its carbon emissions.

Chinese leader Xi Jinping is not attending COP26 in person, and is due to send a written message to delegates on Monday instead.

Sullivan said China was not fulfilling its "end of the bargain" by failing to attend the summit, Reuters reported.

"They are a big country, with a lot of resources and a lot of capabilities, and they are perfectly well capable of living up to their responsibilities," he said, according to the news agency.

— Chloe Taylor

07:13 am: Who’s attending COP26?

World leaders from more than 100 countries are convening in the Scottish city of Glasgow for the U.N.'s 26th COP summit.

The event is widely regarded as a make-or-break moment to take meaningful action on limiting global warming.

Those attending the event in person include: U.K. Prime Minister Boris Johnson; U.S. President Joe Biden; Australian Prime Minister Scott Morrison; European Commission President Ursula von der Leyen; Democratic Republic of Congo President and Chair of the African Union Felix Tshisekedi; and former Bank of England Governor Mark Carney, who is now the U.N.'s special envoy on climate action and finance.

— Sam Meredith

06:40 am: Russia’s Putin won't address COP26 live

Russian President Vladimir Putin, who is not attending COP26, will not speak live at the summit, the Kremlin confirmed Monday.

Spokesman Dmitry Peskov said it would not be feasible for Putin to address delegates live, and he would instead send a recorded video message, Reuters reported.

Chinese leader Xi Jinping, who is also not attending COP26 in person, is due to send a written message to the conference on Monday. Russia and China's absence from the event have been viewed as a big blow to hopes for significant progress on reducing global emissions.

— Chloe Taylor

05:35 am: U.N.’s Topping: Tackling warming about interplay between policy and private sector

Speaking to CNBC's Steve Sedgwick, U.N. Climate Champion Nigel Topping said the "real dynamism and implementation [of the green revolution] will come from the private sector, but it needs the guiderails of policy."

— Chloe Taylor

05:26 am: What’s at stake at COP26?

To have any chance of capping global heating to 1.5 degrees Celsius above pre-industrial levels, the aspirational goal of the 2015 Paris Agreement, the world needs to almost halve greenhouse gas emissions in the next 8 years and reach net-zero emissions by 2050.

Climate scientists have repeatedly stressed that the best weapon to tackle rising global temperatures is to cut greenhouse gas emissions — fast.

One expert told CNBC ahead of the summit in Glasgow that at least 195 countries must commit to net zero targets by 2050 at the latest. Meanwhile, a climate lawyer said COP26 must trigger a profound "justice reset."

— Sam Meredith

04:58 am: COP26 a ‘minute to midnight moment,’ U.K.’s Johnson says

Speaking to the BBC, British Prime Minister Boris Johnson said COP26 marked a "one minute to midnight moment."

"The clock is ticking – we have to get everybody to do more and make further commitments," he said.

Those commitments need to include actions like moving away from the use of fossil fuels, using electric vehicles and planting millions, if not a trillion, trees around the world, he added.

"Above all, [we need to work out] how we're going to get the whole of the developing world to buy into all of this," Johnson said.

— Chloe Taylor

04:54 am: U.K.'s Johnson lays out plans for climate summit

British leader Boris Johnson outlines what he'll be demanding from his peers at COP26.

04:38 am: Scottish leader Sturgeon urges leaders to act

Nicola Sturgeon, first minister of Scotland — where COP26 is being held — said Monday morning that she hoped world leaders would "step up" at the summit.

— Chloe Taylor

04:25 am: What’s on Monday’s agenda?

The summit's opening ceremony will take place at midday Glasgow time (8:00 am ET). Statements from heads of state and heads of government will be heard between 1:45 pm and around 5:00 pm local time.

U.S. President Joe Biden is scheduled to speak on Monday. Other speakers include French President Emmanuel Macron, Indian Prime Minister Narendra Modi, European Commission President Ursula von der Leyen and German Chancellor Angela Merkel.

Chinese leader Xi Jinping, who is not attending the summit, will address delegates via a written statement on Monday.

Monday will also see some closed meetings take place.

— Chloe Taylor

03:27 am: G-20 leaders pledge climate action with few concrete commitments

Leaders of the world's wealthiest countries met in Rome over the weekend, where they said they "agreed upon a shared vision to combat climate change" and were committed to "work collectively to achieve a successful COP26 in Glasgow."

But the G-20 nations — whose members account for more than 80% of global GDP — were accused by environmental groups of failing to take tangible action on limiting global warming. "I leave Rome with my hopes unfulfilled — but at least they are not buried," António Guterres, U.N. secretary-general said on Twitter.

G-20 members include Australia, Saudi Arabia, the EU, the U.S., and the United Kingdom. U.S. President Joe Biden said during the summit that fellow members China and Russia "basically didn't show up" when it came to tackling climate issues.

— Chloe Taylor

02:55 am: Britain’s Johnson says COP26 ‘cannot let future generations down’

Taking to Twitter, U.K. Prime Minister Boris Johnson argues world leaders will be remembered for what they achieve — or fail to achieve — at the COP26 summit.

— Chloe Taylor

02:42 am: What is COP26?

In 1992, more than 150 countries signed the United Nations Framework Convention on Climate Change (UNFCCC).

Every year, delegations from countries signed to the convention gather for the Conference of the Parties, known as COP.

The first COP was held in Berlin in 1995. More than 25 years later, the Scottish city of Glasgow is hosting COP26.

Watch the video below to find out what happens at COP and the role it plays in the fight against climate change. 

— Tom Chitty