RIO DE JANEIRO — Japan on Wednesday pledged $6 billion in aid over the next three years to help developing countries make the transition to a "green economy" and reduce potential disaster losses.

The pledge was announced by Foreign Minister Koichiro Genba at the U.N. Conference on Sustainable Development, or Rio+20, in Rio de Janeiro.

Japan's aid programs, which will start from 2013, will focus on three areas — the promotion of urban planning with advanced green technologies, the development of human resources in the field of environmental policy, and disaster reduction.

"Today, with the diversification of actors in the international community, we must move beyond the old dichotomy of 'developed countries' and 'developing countries' and have all stakeholders unite their strengths toward the common interests of global sustainable development," Genba said.