ALOK Sharma has warned that fostering success at COP26 is “a very big, tough ask” - as he called on world leaders to “leave the ghosts of the past behind” and focus on fixing the climate crisis.

COP26 will officially open today before the two-day world leaders’ summit begins on Monday.

Speaking on Sky News, Mr Sharma, the president-designate of COP26, warned that what is required in Glasgow is perhaps more difficult than the agreement reached in Paris which committed nations to limit global warming to 2C with the ambition of 1.5C.

He said: “This is obviously a very big, tough ask that we have got here in Glasgow.

“There has been progress over the last few years but I would say that actually the task we have here is in many ways tougher than Paris.

“Paris was a brilliant achievement, a historic achievement, but as a framework agreement.

“What we’ve had to do since then is agree some of the detailed rules and some of the most difficult rules are still outstanding after six years, and that makes it really challenging.

“Of course, we know that the geopolitics is more difficult than it was at the time of Paris.”

Mr Sharma added that the pressure was on world leaders to thrash out an agreement and make COP26 a success.

He said: “My message to them is very clear - leave the ghosts of the past behind you – it is Halloween today, after all.

“Let’s focus on the future and unite around this one issue we know that matters for all of us, which is protecting our precious planet.”

Asked about the Prime Minister striking a less than optimistic tone about the prospects of success at the summit, Mr Sharma said: “The Prime Minister is absolutely right, it is going to be really tough at this summit.

“We’ve got two weeks to get this over the line.

"But he was also making the point that when we took on the presidency of COP26, less than 30% of the economy was covered by a net zero target – we are now at over 80%, nearly all the G20 nations have a net zero target for the middle of the century.

“If I’d come on to this programme a year ago and said that you would have been really sceptical, so there has been progress, but there is much more to do.”

Speaking later on the BBC's Andrew Marr Show, Mr Sharma said failing to limit global warming to 1.5C would be "catastrophic" for many countries and communities around the world.

He added: "This is on leaders.

"They ned to come forward and collectively agree how we can adress this gap."

Mr Sharma was asked about the barriers in the United States legislature hoding up President Biden's strategy to cut emissions and whether it was a threat to COP26 being a success.

The COP26 president said he welcomed a US adminsitration that was "totally focued on climate change" and stressed it was vital to "ensure the US system delivers for the planet".

Lord Deben, the chairman of the UK Government’s independent advisers, the Climate Change Committee, told Sky News that COP26 is “the one chance we have to save the world”. 

He added that the 1.5C ambition “has to be attainable”, adding that it is “a battle that we just have to win”. 

Lord Deben said: “Like the Battle of Britain, we cannot lose it.”