“It’s high time we rise together. Do one thing for another human being. Nothing is too small. Make your mark, and say ‘I was here’.”

So says Beyoncé, lending her fierce star power to a just-launched campaign for the United Nations on Humanitarian Day 2012, happening on Sunday August 19.

The singer will also release a special video for her touching song I Was Here on that same day – the clip will be filmed in the UN General Assembly Hall in New York in front of a live audience.

Songwriter Diane Warren and Beyoncé have dedicated the video to the international humanitarian campaign, which aims to get one billion people around the globe active on that day, sharing actions and stories of goodwill from all walks of life.

“We all see the headlines, and we think, what can I really do to help?” she says. “World Humanitarian Day is an opportunity for all of us to work together to make a difference.

“This is our time to leave our mark on the world and show that we were here and we care.”

Check out Beyoncé on the video below and discover more about the campaign here.