New Delhi, Apr 10 (IANS): Emphasising that India has nearly 17 percent of the world's population but only four percent of its usable fresh water, Prime Minister Manmohan Singh Tuesday called for a legal framework to govern the use of groundwater.

Speaking at the inauguration of India Water Week at Vigyan Bhavan here, Manmohan Singh said conserving groundwater was an urgent priority.

"We should also examine seriously the proposal to have a clear legal framework to govern the use of groundwater. Conserving our groundwater is now an urgent priority because we depend on it for more than two thirds of our water needs," he said.

The prime minister also called for management of irrigation systems in the country.

"With nearly 17 percent of world's population and only four percent of its usable fresh water, India has scarcity of water. Our irrigation system should move away from a narrow engineering approach to a multi-disciplinary, participatory approach," he said.

Manmohan Singh said the National Water Mission sets a target of 20 percent improvement in water use efficiency, which is critical for the agricultural sector.

India Water Week, being organised for the first time, will focus on water issues and provide a global platform for related issues that brings policy makers, industry and experts together.

Around 1,000 participants from India and around 43 from abroad are taking part, said officials.