WATCH: 80,000 answer One Direction's call to action

The band launched their 'action/1D' campaign, calling on fans to make their voices heard on issues such as poverty and inequality, and more than 80,000 people from 172 countries responded.

The result is Dear World Leaders, a three-minute film the band hopes will raise awareness of global issues.

Directioners were asked to submit pictures and videos which the group then used to piece together the film and put pressure on world leaders.

The resulting film, which was released on Monday, is made up of a montage of pictures and videos from fans as far afield as Malaysia, New Zealand, Germany and South Africa.

Introducing the video, Wolverhampton's Liam Payne says: "Dear world leaders, we asked our amazing fans what sort of world they wanted to live in in the future and they responded in their thousands."

Harry Styles adds: "They were thoughtful, creative and above all, very passionate."

Louis Tomlinson also says: "We think you should hear what they have to say about the future of their world."

During the video, fans talk about issues including education, race, human rights, women's rights, the environment and eradicating poverty and hunger.

Access to clean drinking water and protecting the environment are also discussed, before one Directioner finishes with the statement: "The world is not perfect, but if this video provides a chance for all of us to unite and make a change, then it's a chance worth taking."

As the video, which has already been watched more than 945,000 times, was released, former St Peter's Collegiate student Liam, from Bushbury, tweeted: "Really proud of how our Action 1D film turned out. Thank you to everyone who was involved!"

Margherita Watt, director of creative and digital at Save the Children, said: "One Direction has done an incredible thing by mobilising their huge fanbase to speak up about the issues that really matter to them in this momentous year.

"We hope that by speaking out together, their voices will be heard and in a way that world leaders cannot ignore. This is the generation that has the power to tackle the most important issues of our time and change the world for better."