91Èȱ¬

Sir David Attenborough has said he cheered when he found out US President-elect Joe Biden plans to rejoin the Paris Agreement on climate change.

The Paris Agreement is a huge international deal to do something about climate change agreed in 2016 by leaders from 195 countries - including Barack Obama, who was the US president at the time.

In 2017 President Donald Trump announced he was pulling America out of the Paris Agreement on climate change because he didn't think it was a good deal for US citizens.

Sir David said the moment he realised Mr Biden was to win the presidency and would rejoin the Paris Agreement, was the first time he'd ever cheered at the result of an election.

Speaking ahead of the launch of his new TV series he said: "I can't remember actually getting out of my seat and cheering all by myself until that moment.

"I mean, I've never done it before, even on our own elections."

Under the Paris Agreement, countries have committed to keep global warming to below 2C, and to try and limit it to 1.5C.

Apart from China, the US produces the most greenhouse gases of any country in the world. These gases can contribute to climate change.

Sir David said he has seen "a very strong element in the United States that does not believe [in the need to act on climate change] - including the past president [Donald Trump]."

The-94-year-old, who regularly speaks out on environmental issues, has warned that the planet is "facing a real crisis".

He said: "If we warm the Earth to such a degree that the Arctic melts, every city in the world - every big city in the world, very nearly, will be underwater."

"A high proportion of the important cities in the world are built around the coast because of their ports and... if the northern Arctic melts, the seas are going to rise and flood those cities.

"That's not imagination, it's not science fiction, it's going to happen and we have still got a chance to stop it happening."

Next month a new natural history series called A Perfect Planet presented by Sir David will air on 91Èȱ¬ One from 3 January.

It will explore the impact of natural phenomena such as sunlight, volcanoes, weather and oceans on Earth, as well as humans impact on the planet.