COP26: Sir David Attenborough warns world leaders must act now or 'it'll be too late' for planet

Sir David Attenborough has warned world leaders must act now on climate change or "it'll be too late" for the planet.

He added it would be "really catastrophic" to ignore the issue.

His comments come ahead of the COP26 conference in Glasgow, which starts on Sunday and has been billed as the last best chance to keep global temperature rises to no more than 1.5 degrees Celsius.

Insulate Britain asks people to obey its 20mph speed limit on M25 from 7am on Wednesday - climate latest

In conversation with BBC science editor David Shukman, the veteran broadcaster said: "Every month that passes, it becomes more and more incontrovertible, the changes to the planet that we are responsible for that are having these devastating effects."

He added: "If we don't act now, it will be too late. We have to do it now."

The 95-year-old said wealthier western countries have a "moral responsibility" to help refugees displaced by climate change.

"We caused it - our kind of industrialisation is one of the major factors in producing this change in climate. So we have a moral responsibility," he told the BBC during filming for his new series, The Green Planet, which will air on BBC1 next year.

"Even if we didn't cause it, we would have a moral responsibility to do something about thousands of men, women and children who've lost everything, everything.

"Can we just say goodbye and say this is no business of ours?"

Sir David will be present at the summit and has previously been a vocal critic of those who deny climate change.

Earlier in October, he said the possibilities of COP26 gave him "some hope".

"For the first time people around the world will hear the arguments as to what we should do, the analyses as to what the problems are and what the solutions are," he said.

"Those two things bring me some hope."

However, Prime Minister Boris Johnson has said he is "very worried" the conference might not secure the agreements needed, admitting it is "touch and go".

Subscribe to ClimateCast on Spotify, Apple Podcasts, or Spreaker.

When answering questions from school children around the world, he said: "It is going to be very, very tough this summit.

"I am very worried because it might go wrong and we might not get the agreements that we need and it is touch and go, it is very, very difficult, but I think it can be done."

Watch the Daily Climate Show at 6.30pm Monday to Friday on Sky News, the Sky News website and app, on YouTube and Twitter.

The show investigates how global warming is changing our landscape and highlights solutions to the crisis.