Malaysia is drafting new laws to require homes and buildings to collect rainwater in a bid to conserve water supplies, reports said Wednesday.

Newspapers quoted Prime Minister Abdullah Ahmad Badawi saying the move was part of an energy efficiency drive to save costs and to minimise the use of treated water for human consumption only.

"It is a sheer waste for treated water to be used to wash cars or water plants when it should be used for bathing, for instance," Abdullah was quoted as saying in the New Straits Times.

Abdullah also said the government through its water resources council had decided on a study to identify underground water resources.

Concern has been growing over the state of Malaysia's rivers, which are suffering increasing pollution from industrial activities and development.

A sustainable water conference in Malaysia this week heard that the country's demand for water is projected to increase by 63 percent from 2000 to 2050, according to the Bernama news agency.