That's the warning in a report by the InterAction Council, a group of 40 prominent former government leaders and heads of state, working with the United Nations University's Institute for Water, Environment and Health, and Canada's Walter and Duncan Gordon Foundation.
"The future political impact of water scarcity may be devastating," former Canadian Prime Minister and council Co-chairman Jean Chretien said in an IAC release Monday.
"Using water the way we have in the past simply will not sustain humanity in future. The IAC is calling on the United Nations Security Council to recognize water as one of the top security concerns facing the global community."
The report focused on the danger in many regions, particularly sub-Saharan Africa or West Asia and North Africa, where critical water shortages already exist.
"As some of these nations are already politically unstable, such crises may have regional repercussions that extend well beyond their political boundaries," IAC member and former Norwegian Prime Minister Gro Harlem Brundtland said.
Water demand in India and China, the world's two most populous countries, will exceed supplies in less than 20 years, the report warns.