“Conditions in slums are a violation of human rights,” Mr. Ban said in a message to the fifth session of the World Urban Forum, which got under way in the Brazilian city of Rio de Janeiro.

“The children who have no clean water, the women who fear for their safety, the young people who have no chance to receive a decent education have a right to better, and we have a responsibility to do better [to help them],” said Mr. Ban.

The Forum was established by the United Nations to examine the effects of rapid urbanization on communities, cities, economies and the climate. It held its first meeting in Nairobi, Kenya, in 2002.

The Secretary-General noted that an estimated 22 million people in developing countries had managed to move out of slums each year during the past decade, but that achievement was not enough to have the impact required to reduce urban poverty.

According to the United Nations Human Settlements Programme (UN-HABITAT), the number of people living in slums rose from 777 million in 2000 to almost 830 million in 2010.

“All people have the right to safe drinking water, sanitation, shelter and basic services. All people have the right to live with a sense of security. All people should have the opportunity to work for a better future,” the Secretary-General said.

“Your plan to launch the World Urban Campaign will advance our work to reach these life-saving goals,” Mr. Ban told delegates.

The World Urban Campaign is a platform for public, private and civil society actors to discuss policies and share practical tools for sustainable urbanization.