Roar singer Katy Perry has joined forces with UNICEF to star in a new video, calling for action on climate change and raising awareness of the extreme weather patterns emerging across the world, forcing millions of children and families to flee their homes.

Perry commented 'Droughts, floods, heatwaves and other severe weather conditions are putting children at an increased risk of disease and malnutrition, as well as destroying their families' homes and livelihoods. Let's encourage our world leaders to take this issue seriously. Share your story on how you are helping reduce climate change with the hashtag #FightUnfair. Together we can help change the forecast for millions of children'.