This year’s event focuses on the link between harming the natural world and disease outbreaks like Covid-19

Cities around the world were turning off their lights on Saturday for Earth Hour, with this year’s event highlighting the link between the destruction of nature and increasing outbreaks of diseases like Covid-19.

In London, the Houses of Parliament, London Eye, Shard skyscraper and neon signs of Piccadilly Circus were among the landmarks flicking the switches.