UN Secretary-general Ban Ki-moon on Thursday called for a more intelligent use and less waste of water resources, as well as better water cooperation to promote sustainable development.

"Water holds the key to sustainable development. We need it for health, food security and economic progress," Ban said in a message marking the World Water Day, which falls on Friday.

In the message, the UN chief warned: "One in three people already lives in a country with moderate to high water stress, and by 2030 nearly half the global population could be facing water scarcity."

More than half of the world population depend daily on water resources shared by more than one country, and 90 percent of the global population live in countries that share river or lake basins. However, 60 percent of the world's 276 international river basins lack any type of cooperative management framework, according to UN figures.

"Climate change and the needs of populations growing in size and prosperity mean we must work together to protect and manage this fragile, finite resource," Ban said. "Agriculture is by far the largest user of freshwater, and there is growing urgency to reconcile its demands with the needs of domestic and industrial uses, especially energy production."

This year is the International Year of Water Cooperation, which seeks to provide a platform for countries to collaborate in the management of water resources in the interest of peace and development.

The UN General Assembly proclaimed the year in 2010, following a proposal from Tajikistan. It is expected to raise awareness and prompt action on the multiple dimensions of water cooperation, such as sustainable and economic development, climate change and food security.

"We cannot prosper without clean, plentiful freshwater," Ban stressed. "Let us use it more intelligently and waste less so all get a fair share."