Major polluting countries must deliver on their promise to put forward more ambitious plans to tackle climate change ahead of Cop26, the summit’s president has urged.

With a month to go until the UN conference in Glasgow, which aims to curb dangerous global temperature rises, Alok Sharma warned countries have not delivered all the needed commitments on emissions cuts or finance.

The Cop26 President said the “ball is in the court” of countries such as China to unveil stronger action to cut pollution for this decade.

Mr Sharma also said he is continuing to press developed nations to deliver a long-promised 100 billion US dollars (£74 billion) a year to help poorer countries tackle climate change.

His comments come after a UN report on the national action plans put forward by countries to meet the goals of the global Paris Agreement to curb temperature rises to well below 2C and pursue efforts to limit them to 1.5C.

It found current plans for cutting greenhouse gas leave the world well off track to meet its goals, with projected emissions rises of 16% on 2010 levels by 2030, instead of falling by nearly half as required to meet the tougher 1.5C goal.

Speaking to the PA news agency, Mr Sharma acknowledged the report from the UN was “really very sobering”.

But he said countries that have raised ambition, such as the UK, are bending the curve downwards.

Some of the biggest emitters, such as China and India, have not put forward new action plans, which they promised to do before Cop26 as part of a communique from the G20 group of leading nations earlier this year.

“The ball is in the court of every G20 country that has not come forward, and we need to see them deliver on their promise,” Mr Sharma said.

He also said there is some way to go on delivering the 100 billion US dollars a year in climate finance after an OECD report showed money flowing to developing countries was just under 80 billion US dollars in 2019.

Asked if climate campaigner Greta Thunberg’s criticism this week of “blah blah blah” from leaders saying the right things but not delivering action is fair, Mr Sharma said: “We haven’t got all the commitments we need.

“That’s very clear. I think that was made very clear by these reports that we’ve had on the emissions reduction targets, that we’ve had on the amount of finance.

“So it’s absolutely right that we continue to press the donor countries to do more, and we continue to press all countries, particularly the biggest emitters, to do more.”

He also said if governments fail to deliver at Cop26, future generations will hold them to account.

The Glasgow conference has been billed as crucial to delivering the goals of the Paris Agreement which, when it was agreed in 2015, recognised countries needed to significantly increase action to cut greenhouse gases.

But the while the gap between meeting the temperature goals, intended to stave off the most dangerous impacts of global warming, and action has reduced since Paris, it is not set to be closed by next month’s summit.

Mr Sharma said: “Glasgow is, if I can use a footballing analogy, a really important match in the league.

“What we are ultimately doing is fighting to keep the ambition towards 1.5C alive.”

He said countries will collectively have to set out at Cop26 how they will close the gap between commitments and where the world needs to be at the end of the decade.

Despite a gap in climate finance and the context of Covid-19, including the inequality of the global vaccine rollout, potentially souring the atmosphere at the talks, Mr Sharma said every country he has spoken to wants to see Cop26 as a success.

“People around the world recognise that climate is a big leveller, it doesn’t recognise borders, it is affecting absolutely every single country on Earth, and that’s why we need to work together collectively on this.

“We are already at 1.2C of average global warming, and I think for very many people that may not sound a lot, but you are seeing the impacts of that literally being felt in every country around the world.

“In just the last few months, you’ve seen terrible flooding in China, loss of life, you’ve seen the flooding in central Europe, wildfires in North America, we’ve seen record temperatures in Europe.”

Madagascar is experiencing climate-induced famine, while Barbuda, which was devastated by Hurricane Irma in 2017, has had little restoration and community leaders there warn many people who lived there have left.

“You’ve effectively seen forced migration which, unfortunately, is going to get worse around the world unless we tackle climate change,” Mr Sharma said.

He said he believes the world is “past the inflection point” in the shift to a green economy but must go faster with action.

“I think we’ve gone past the inflection point, actually, where businesses, civil society and governments are effectively speaking from the same book on this issue,” he said, pointing to companies signing up to emissions cutting targets and investing in green projects and technology.

“For me the issue isn’t that we are seeing the energy transition, the green transition, taking place.

“I think the issue is we need to go faster, and this is where we need to make sure every country is stepping up.”

As a result, Cop26 will be focusing on areas such as ending the use of coal, moving to selling only ultra low emissions cars, ending net deforestation by 2030, and taking action on the powerful but short-lived greenhouse gas methane, he said.

The Government is expected to publish its strategy for cutting emissions to zero overall by 2050 before next month’s conference, and Mr Sharma acknowledged people will be watching what the UK is doing to tackle climate change – but said the country is perceived as a leader.

He added: “I think it’s a good thing that every country is looking to see what everybody else is doing, and hopefully rising to the challenge of matching the ambition around the world.”