Former Archbishop of Cape Town and international human rights and peace activist, Desmond Tutu, is to be the voice of relief and development charity World Vision's latest Child Sponsorship Appeal later this month.

The 79-year-old will appeal to Londoners in adverts on television, the press and posters on the London Underground from 21 April to 2 May calling them to 'Sponsor a child with World Vision and give a child joy'.

By the Archbishop lending his support to this campaign, World Vision hopes to engage Londoners in a fresh approach to tackling the causes of poverty and through sponsorship transforming the lives of thousands of children in poor communities overseas.

In the advert the Archbishop appeals directly to viewers, stating, "Inside us all is something strong enough to change the world. To refresh those without water, to care for the sick, to give a child joy - one small act of goodwill. It's inside us all.

"Can you find it in your heart? Please sponsor a child with World Vision and stand with me as a World Vision goodwill ambassador. Because in one child's eyes, your goodwill will change the whole world."

World Vision's Head of Consumer Marketing, James Mooring said, "We feel very privileged that Archbishop Tutu is lending his support for the World Vision appeal for sponsors.

"This is a man who has dedicated his life to fighting injustice in all its forms not only at home in South Africa, but around the world. I believe that in the words of the Archbishop, 'Londoners have a big heart' and can show the world how big it is by responding to his call to sponsor a child with World Vision, thereby joining us in the fight against poverty."