New Delhi: Magsaysay award-winner 'Waterman' Rajendra Singh and two others on Saturday quit the Prime Minister Manmohan Singh-chaired National Ganga River Basin Authority (NGRBA), protesting the government's "negligence" of the river.

Besides Singh, two other NGRBA members Ravi Chopra and R H Siddiqi also submitted their resignation letters to Prime Minister Manmohan Singh expressing solidarity with noted environmentalist G D Agrawal who is on "fast-unto-death" to press for cleaning up the Ganges.

Rajendra Singh said that the resignations were sent after their meeting with Water Resources Minister Pawan Kumar Bansal during the day when they apprised him of the agitation of Agrawal, who is known as Swami Gyanswaroop Anand.

Agrawal had on Friday announced that he will not take water in the last phase of his fast-unto-death to press for uninterrupted clean flow of the Ganga.

While Chopra is the Director of Dehradun-based People's Science Institute, Siddiqi is a former Professor of Aligarh Muslim University.

Several Union Ministers -- Finance, Environment, Urban Development, Water Resources, Power, Science and Technolgy-- and Planning Commission Deputy Chariman are the ex-officio members of NGRBA.

Other ex-officio members include Chief Ministers of Uttarakhand, Uttar Pradesh, Bihar, Jharkhand and West Bengal, the states through which the river flows.

Besides Rajendra Singh, Ravi Chopra and R H Siddiqi, there are six other expert members in the committee including noted environmentalist Sunita Narain.

National Ganga River Basin Authority was constituted on February 20, 2009, under Section 3(3) of the Environment (Protection) Act, 1986.

The objective of NGRBA is to ensure effective control of pollution and conservation of the river by adopting a river-basin approach for comprehensive planning and management.

The Authority has both regulatory and developmental functions. The Authority is also to take measures for effective abatement of pollution and conservation of the river Ganga in keeping with sustainable development needs.