'I know that the climate crisis and the destruction of nature can feel overwhelming at times, but I promise you when millions of people stand together, and demand change, the dial begins to shift.
The blonde beauty will join actress Maisie Williams who announced her role as an ambassador last year.'I am honoured and excited to be working with WWF where together we will give the opportunity for people to learn about critical parts of the natural world that are most at risk, and how we can all personally make a difference and preserve them for future generations'.
Incredible: The star is already known for her long-standing relationship with the organisation, including a visit to Greenland's Jakobshavn glacier with climatologists where she saw the rapid rate of ice loss first hand Tanya Steele, chief executive of WWF-UK, said: 'We're delighted to welcome Ellie as an ambassador at such a crucial time.
'Earth Hour reminds us that when millions of people come together, small actions can make a big difference.