Boris Johnson has warned that success in the fight to tackle global warming “is going to very difficult” but “the whole of humanity is in the ring.”

Imploring world leaders to act as the G20 summit begins in Rome on Saturday, the prime minister told Sky News’ Beth Rigby there is “a chance, if everybody puts their minds to it” that an agreement on climate change can be achieved.

But, acknowledging the scale of the challenge ahead, the PM added that global temperature rises will not be stopped at the two-week long COP26 climate summit which kicks off in Glasgow on Sunday.

The PM’s comments come a day after he told journalists en route to the first of the global gatherings in Rome that “team world” was “5-1” down at half-time in the battle to save the planet.

Mr Johnson also stressed the alternative to securing change was apocalyptic and could consign future generations to shortages of food, conflict and mass migrations, all caused by global warming.

Speaking to reporters at the Colosseum on Saturday morning, the PM once more acknowledged that “the pressure is huge”.

Asked if he is fighting a losing battle, the PM told Sky News: “Well, the whole of humanity is in the ring. And the foes of humanity are apathy and political indifference and lack of will and people’s excessive caution about what they can achieve. Those are the foes that we all collectively face.

“And actually, I think that we can still do it. I think there is a chance, if everybody puts their minds to it, that we can get an agreement that will allow us to restrain the growth in temperatures.

“We are not going to stop climate change… we are certainly not going to stop it at COP next week.”

Mr Johnson said the odds of success remain “about the same” as they were when he made his football analogy to reporters on Friday, noting that the task ahead is “going to be very difficult”.

“Let’s see where we get to and the pressure is huge – but what people need to do is see the scale of the risk,” the PM said, referencing the rise and fall of the Roman Empire.

Mr Johnson acknowledged that China has made “a huge amount of progress in some areas” but warned that “what we want to see is more progress from lots of countries”.

“We can fix it, but the lesson of history is that things can go badly wrong and stay wrong for a long time,” the PM continued.

With 80% of all global emissions coming from the G20 group of industrialised countries, progress this week in Rome is seen as critical to the success of COP26, the annual climate summit in Glasgow which is meant to put in place national commitments from individual countries to hit emission targets of 2% and below by 2050.

Earlier this month, Alok Sharma, the UK’s COP president, challenged China, India and Saudi Arabia to deliver on G20 promises made months ago and come up with better formal targets in an interview with the Financial Times.

On Friday, the PM stressed progress was being made, with 17 nations of the G20 now committing to net-zero by 2050.

But two of the top three of the world’s largest emitters – China and India – have so far failed to commit to getting to net-zero by 2050.

Some have raised concerns that while the UK is pledging to do its bit in the fight against climate change, the country accounts for just 1% of global emissions.

And of the three biggest emitters – China, the US and India – only the US has made similar promises.

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President Modi of India has resisted formal targets while there are concerns that President Xi of China is not going far enough.

China has committed to peak carbon emissions before 2030 and net-zero by 2060, but has indicated it is both unable and unwilling to move further.

US special envoy on climate change John Kerry has said the world will miss its global emissions targets unless this happens.

The PM said he spoke to President Xi on Friday and pushed the Chinese leader to bring down the peak in emissions to 2025 and to phase out coal.

“I told President Xi, when I first went to Beijing as Mayor of London, we had 40% of our energy come from coal. It is now less than 1%,” Mr Johnson told Beth Rigby.

This year’s UN Climate Change Conference, better known as COP26, kicks off this weekend and will see more than 190 countries come together in Glasgow to discuss the climate crisis.

This year’s summit is particularly important as it will be the first time the parties will review the most up-to-date plans for how they will limit global warming to 2C but ideally 1.5C, a goal set under the Paris Agreement at COP21.

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