Lifestyles in the developed world will have to change if the planet is to remain habitable, U.N. Secretary-General Kofi Annan has said. Speaking on Monday at the London School of Economics, Annan said the World Summit on Sustainable Development, to be held South Africa later this year, "must mark a break with business as usual." The summit will offer heads of state, business leaders and pressure groups a chance to agree on practical ways to reduce poverty, expand access to fresh water and sanitation, and adopt cleaner and more efficient use of energy.