LONDON-If the Glasgow climate conference fails to deliver, it could mark the end of the global approach to tackling the problem.

COP26 in November will see around 200 world leaders meet to agree a new, long term deal on rising temperatures. But according to Claire O’Neill, the president of COP26, the UK has “one shot” at making it a success.

She told a BBC documentary that if Glasgow fails, people will question the whole UN approach. COP26 marks a critical moment for the UN in the long running effort to find a global solution to climate change.

Another 120 countries have now told the UN that they have either agreed on plans to reach net-zero emissions by 2050 or are working towards that goal. While this represents some progress, a key part of the Glasgow meeting will be trying to push countries to go even further.

In December, there was widespread dismay after countries failed to agree on more ambitious steps at the Madrid conference of the parties known as COP25.

The messy compromise in the Spanish capital has also left a raft of complex issues unresolved, including the use of carbon markets, plus the question of compensation for loss and damage suffered by poorer nations from storms and rising sea levels.

Underpinning the lack of progress in Madrid was the huge gap between big emitters such as Brazil, Australia, India, China and US and an alliance of countries wanting to go much faster including the European Union, small island states and vulnerable nations.

Former UK minister Claire O’Neill has been tasked with presiding over COP26 and delivering an agreement acceptable to all. UN talks in Madrid ended in disappointment with many decisions kicked down the road

Widely seen as knowledgeable and authoritative, Ms O’Neill says that Glasgow is the best, and perhaps last chance to make progress under the long drawn out UN process.

“I think we have one shot,” she said, speaking to the BBC at the end of the Madrid conference in December.

“I think if we don’t have a successful outcome next year people will legitimately look at us and say ‘what are you doing, is there a better way?’”

“I think we have this amazing opportunity to get the world together to talk about ambition but crucially to deliver it, and I guess I am really determined to do that.”

Leipzig the key?

Scientists say that to keep the rise in global temperatures under 1.5C this century, a major upgrade is needed on the plans that countries are already applying to the problem. Delivering anything close to that type of deal in Glasgow will depend on a number of key meetings in the run up to COP26.

One of the most important is the summit between the President of China, Xi Jinping and EU leaders in Leipzig in September.