One in three people in the world is suffering from some sort of water shortage, according to a study out today.

The Comprehensive Assessment of Water Management in Agriculture shows that we are already suffering water scarcity levels previously predicted for 2025.

The findings were released during World Water Week in Stockholm.

Frank Rijsberman, director general of the International Water Management Institute (IWMI), said: "Predictions in 2000 had forecast that one third of the world population would be affected by water scarcity by 2025. Our findings from the just-concluded research show the situation to be even worse.

"Already in 2005, more than a third of the world population is affected by water scarcity. We will have to change business as usual in order to deal with growing scarcity of water crises we see in some countries such as India, China and the Colorado River basin of the USA and Mexico."

The assessment was carried out by 700 experts from around the world over the past five years.