The coverage on this live blog is now over.

International lawmakers, business leaders and activists convened in Glasgow, U.K. on Wednesday in the final week of the COP26 climate summit.

Delegates have been asked to accelerate action on climate change and commit to more ambitious cuts in greenhouse gas emissions, all in an effort to limit global temperature rises.

Here are some of the biggest developments Wednesday:

• UN climate agency publishes draft of COP26 deal{

  2:40a.m.: UN climate agency publishes draft of COP26 deal

  

  The UN's climate agency has published a first draft of the political decision countries will issue at the end of the COP26 summit.

  Negotiators from nearly 200 countries will work from the draft, known as the "cover decision," to strike a final deal before the summit ends on Friday, Reuters noted.
  
  The seven-page draft agreement focuses on adaptation — helping countries deal with the effects of climate change — and finance, a controversial issue because poorer countries accuse richer countries of not contributing enough to help them tackle climate change.
  
  The draft decision calls on countries to "revisit and strengthen the 2030 targets in their nationally-determined contributions, as necessary to align with the Paris Agreement temperature goal by the end of 2022."
  
  It also emphasized "the importance of multilateralism ... and the crucial role of international cooperation" in tackling climate change and includes sections addressing science, adaptation, mitigation and finance and technology, among others.
  
  The final deal will be closely watched for how ambitious its commitments are with critics saying the agreement is not likely to go far enough.
  
  — Holly Ellyatt

  =null}
• Saudi energy minister says climate fight shouldn't shun any particular energy source{

  6:00 a.m.: Saudi energy minister says climate fight shouldn't shun any particular energy source

  

  Saudi Arabia's Energy Minister Prince Abdulaziz bin Salman Al-Saud has told COP26 on Wednesday that global efforts to fight climate change should not involve the shunning of any particular energy source.

  "It's important that we recognize the diversity of climate solutions ... without any bias towards or against any particular source of energy," he told delegates.
  
  He said the global community needed to pool its efforts to tackle climate change and to help less developed countries "without compromising their sustainable development path."

  Saudi Arabia is one of the world's largest oil producers, alongside Russia and the U.S.

  — Holly Ellyatt

  =null}
• Differences remain at COP26 over how often to update climate pledges, minister says{

  8:00 a.m.: Differences remain at COP26 over how often to update climate pledges, minister says

  Swiss Environment Minister Simonetta Sommaruga said on Wednesday that there are widely differing views among nations at the COP26 summit on the right timeframe for revisiting national carbon emission-reducing commitments.

  "Views still differ widely of course as to what should be the preferred timeframe for NDCs to be applied from 2031 onwards," she said, Reuters reported.

  "Some like five-year cycle, others want to change them after every stocktake, smaller group want more flexibility and to do a 10-year cycle."

  — Holly Ellyatt

  =null}
• Boris Johnson: Frustrating to see countries edge to default on climate policy{

  11:58 a.m.: Boris Johnson: Frustrating to see countries edge to default on climate policy

  

  U.K. Prime Minister Boris Johnson told delegates at COP26 on Wednesday that there was "still a huge amount to do" in the final days of the climate summit.

  He said it had been "very frustrating to see countries that have spent six years conspicuously patting themselves on the back for signing that promissory note in Paris, quietly edging towards default, now that vulnerable nations and future generations are demanding payment here, now in Glasgow."

  Johnson said that following "game-changing" climate policy announcements last week, "we're now firmly in the hard yards, the nuts and bolts of international climate diplomacy, and the negotiations are getting tough."

  "Here in Glasgow the world is closer than it has ever been to signaling the beginning of the end of anthropogenic climate change and it's the greatest gift we can possibly bestow on our children and our grandchildren and generations unborn," Johnson said.

  — Vicky McKeever

  =null}

11:58 a.m.: Boris Johnson: Frustrating to see countries edge to default on climate policy

U.K. Prime Minister Boris Johnson told delegates at COP26 on Wednesday that there was "still a huge amount to do" in the final days of the climate summit.

He said it had been "very frustrating to see countries that have spent six years conspicuously patting themselves on the back for signing that promissory note in Paris, quietly edging towards default, now that vulnerable nations and future generations are demanding payment here, now in Glasgow."

Johnson said that following "game-changing" climate policy announcements last week, "we're now firmly in the hard yards, the nuts and bolts of international climate diplomacy, and the negotiations are getting tough."

"Here in Glasgow the world is closer than it has ever been to signaling the beginning of the end of anthropogenic climate change and it's the greatest gift we can possibly bestow on our children and our grandchildren and generations unborn," Johnson said.

— Vicky McKeever

11:15 a.m.: U.S. Congressman Meeks: 'I see real action' with draft COP26 agreement

U.S. Congressman Gregory Meeks told CNBC on Wednesday that he was "very encouraged" by the draft COP26 climate agreement, which was released earlier that day.

"I see real action, real desires to make an accomplishment here, to come away very successful," he said.

— Vicky McKeever

8:00 a.m.: Differences remain at COP26 over how often to update climate pledges, minister says

Swiss Environment Minister Simonetta Sommaruga said on Wednesday that there are widely differing views among nations at the COP26 summit on the right timeframe for revisiting national carbon emission-reducing commitments.

"Views still differ widely of course as to what should be the preferred timeframe for NDCs to be applied from 2031 onwards," she said, Reuters reported.

"Some like five-year cycle, others want to change them after every stocktake, smaller group want more flexibility and to do a 10-year cycle."

— Holly Ellyatt

6:00 a.m.: Saudi energy minister says climate fight shouldn't shun any particular energy source

Saudi Arabia's Energy Minister Prince Abdulaziz bin Salman Al-Saud has told COP26 on Wednesday that global efforts to fight climate change should not involve the shunning of any particular energy source.

"It's important that we recognize the diversity of climate solutions ... without any bias towards or against any particular source of energy," he told delegates.

He said the global community needed to pool its efforts to tackle climate change and to help less developed countries "without compromising their sustainable development path."

Saudi Arabia is one of the world's largest oil producers, alongside Russia and the U.S.

— Holly Ellyatt

5:30a.m.: We need more infrastructure for electric vehicles, ABB's sustainability chief says

Theodor Swedjemark, chief sustainability officer and member of ABB's executive board, talks to CNBC on the sidelines of the COP26 summit about the infrastructure push needed for electric vehicles.

He also commented on Tesla's pilot program in the Netherlands, in which it will open up its charging network to other electric cars for the first time.

4:10 a.m.: Boris Johnson to urge countries to ‘pull out all the stops’ in final days of summit

U.K. Prime Minister Boris Johnson will call on ministers and negotiators to come together and "bridge the gaps remaining" to reach a consensus at COP26. Johnson is travelling to Glasgow on Wednesday.

Negotiators from 197 parties are in intensive talks to reach agreement on a range of key issues, including a common time frame for national commitments on emissions reductions and agreed methodology for countries to report on their climate action, the U.K. government said in a statement. "These important technical points will help to ensure that commitments are translated into action," it added.

They are also working to agree progress on finance for nations most vulnerable to climate change and to address the issue of loss and damage in developing countries.

In released comments, Prime Minister Boris Johnson said "negotiating teams are doing the hard yards in these final days of COP26 to turn promises into action on climate change. There's still much to do. Today I'll be meeting with ministers and negotiators to hear about where progress has been made and where the gaps must be bridged."

"This is bigger than any one country and it is time for nations to put aside differences and come together for our planet and our people. We need to pull out all the stops if we're going to keep 1.5C within our grasp," he commented..

Johnson will be joined by the UN Secretary General Antonio Guterres in Glasgow and will meet with representatives from the heads of delegations' negotiating teams.

— Holly Ellyatt

3:38a.m.: Draft agreement calls for an accelerated phase out of coal, fossil fuel subsidies — but no end date

The first draft of an agreement at the COP26 climate summit outlines what negotiators hope will be in the final outcome at the end of the week. Nothing is agreed until everything is agreed, however.

The seven-page document, published Wednesday, sets out how countries plan to reach the all-important goal of capping global heating at 1.5 degrees Celsius.

Among many other goals, it sees a recognition that high-income countries must scale up their support for low-income nations to deal with the effects of climate change. This is regarded as a critically important issue to restore global trust.

The draft agreement also calls for countries to accelerate the phase-out of coal and subsidies for fossil fuels. It is thought to be the first time that fossil fuels have been targeted in this way, although it does include specific targets or end dates. The landmark Paris Agreement does not mention fossil fuels.

— Sam Meredith

2:40a.m.: UN climate agency publishes draft of COP26 deal

The UN's climate agency has published a first draft of the political decision countries will issue at the end of the COP26 summit.

Negotiators from nearly 200 countries will work from the draft, known as the "cover decision," to strike a final deal before the summit ends on Friday, Reuters noted.

The seven-page draft agreement focuses on adaptation — helping countries deal with the effects of climate change — and finance, a controversial issue because poorer countries accuse richer countries of not contributing enough to help them tackle climate change.

The draft decision calls on countries to "revisit and strengthen the 2030 targets in their nationally-determined contributions, as necessary to align with the Paris Agreement temperature goal by the end of 2022."

It also emphasized "the importance of multilateralism ... and the crucial role of international cooperation" in tackling climate change and includes sections addressing science, adaptation, mitigation and finance and technology, among others.

The final deal will be closely watched for how ambitious its commitments are with critics saying the agreement is not likely to go far enough.

— Holly Ellyatt

2:00 a.m.: Biden administration is doing a 'great job' tackling climate change, Pelosi says

U.S. House speaker Nancy Pelosi told CNBC on Tuesday that U.S. President Joe Biden has been courageous in handling the U.S.' climate change commitments.

Asked whether the Biden administration is demonstrating enough urgency in tackling climate change, Pelosi said:
 
"I think they're doing a great job. The president has been a leader on this subject since the 80's so he understands the challenge and he has been very persuasive and courageous," she said.

— Holly Ellyatt

2:20a.m.: Greenwashing or viable solution? Europe has a big decision to make on nuclear power

The European Union must decide whether nuclear is a clean source of energy, but the decision is tough with countries divided about the right labelling.

Some EU members, notably France, which have big investments in nuclear and are wary of using gas from Russia see the energy resource as a viable option. Other nations, including Germany, believe it is time to move away from it and are worried about nuclear waste.

It is a long-standing dilemma that the European Commission, the executive arm of the EU, must resolve in the coming weeks. The commission is due to publish its sustainable finance taxonomy — rules that will help clarify to investors what the bloc sees as green investments — as an attempt to boost financing in these areas. Read more on this story here.

— Silvia Amaro

1:28 a.m.: Here's a recap of some of the biggest developments Tuesday

Here's a selection of CNBC's highlights Tuesday:

• The world needs more nuclear energy, French official says{=null}
• COP26 panel focuses on 'keeping 1.5C alive' with the help of science{=null}
• Global warming to hit 2.4 degrees by the end of century, Climate Action Tracker warns{=null}
• Alexandria Ocasio-Cortez: The U.S. is back with a 'fundamentally different approach' to climate policy{=null}

— Holly Ellyatt

1:25 a.m.: What's on Wednesday's agenda?

Good morning and welcome to CNBC's live blog covering the COP26 summit in Glasgow, U.K. Here's what to expect on Wednesday:

Negotiators at the summit are expected to review the first draft of a "Cover Decision" on Wednesday — this refers to the negotiated outcome of the COP26 discussions — which is expected to be released formally on Friday.

The document hopes to tackle discrepancies in the commitments between countries and clarify how declarations will meet the requirements of the 2015 Paris Agreement, which set out to cap global temperature rises.

U.K. Prime Minister Boris Johnson will be back in Glasgow later today and, alongside COP President Alok Sharma, is expected to urge participating nations to make a final push toward concrete action rather than just commitments.

"We have made some good progress over the past week and parties have come to the table with a can-do attitude. And we have agreed substantive outcomes on a range of issues, from gender to agriculture. But we still have a lot to do," Alok Sharma told delegates Tuesday.

"Frankly, on some vital issues, there is still too far between us. And so these next few days we are absolutely going to need to see a change in gear. Like you, I have greatly enjoyed my time in Glasgow so far, but I am sure that we all share a desire to finish on Friday, having agreed an ambitious outcome," he added.

— Holly Ellyatt