SIR David Attenborough is the green poster boy for a crunch climate summit in Britain.
He will drum up global support for COP26 in November.
The Glasgow conference aims to hammer out fresh efforts to save the planet.
Sir David is also set to attend June’s G7 meeting in Cornwall where PM Boris Johnson is hosting US President Joe Biden and other world leaders.
Mr Johnson said yesterday: “Sir David has already inspired millions around the world with his passion and knowledge to act on climate change and protect the planet for future generations.
“There is no better person to build momentum for further change as we approach the COP26 climate summit.
“I am hugely grateful to Sir David for agreeing to be our People’s Advocate.”
'CRIPPLING' CLIMATE CHALLENGES
Sir David, 95, said he was “greatly honoured” to take up the role.
He went on: “There could not be a more important moment that we should have international agreement.”
And the broadcaster said the “crippling” climate challenges facing the world would eclipse even Covid-19, if something was not done soon.
Sir David added: “The epidemic has shown us how crucial it is to find agreement among nations if we are to solve such worldwide problems.
“But the problems that await us within the next five to ten years are even greater.”
Plans for around 30,000 delegates to gather in Scotland could be scuppered by Covid, with calls mounting for the event to be held virtually.
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Climate campaigner Greta Thunberg is among those who want COP26 switched online.
But ministers have discussed jabbing everyone who wants to attend.
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