The world's water consumption will increase by 40 percent over the next two decades and efforts to meet this demand must increase radically, the secretary-general of the 5th World Water Forum said in Istanbul on Tuesday.

Oktay Tabasaran said in his opening speech at the World Water Forum that "water consumption will increase by 40 percent in the coming 20 years, reaching 6.9 trillion cubic meters per year ( compared with the 4.5 trillion used currently), and an amount of 200 billion U.S. dollars must be spent annually in order to afford this."

He said such figures indicated the urgent need for countries to engage in efficient cooperation with each other to address water- related issues.

Some 50 out of the world's 188 countries have serious concerns in providing drinking and irrigation water, due to careless and inefficient use of water, according to Ismail Ugur, the general director of Turkey's State Waterworks Authority.

"If we fail to come up with solutions, starting from 2015 there will be droughts (in many parts of the world) and people will start suffering from diseases caused by lack of water, as of 2025, " Ugur said.

Ekmeleddin Ihsanoglu, head of the Organization of the Islamic Conference (OIC), said that ensuring reliable access to water is crucial to promoting peace and security in the Middle East, where many countries are facing dramatic declines in available water.

"In some regions of the Muslim world, water availability is predicted to be cut in half by 2050, even without taking into consideration the effects of climate change," he said in his opening speech.

The OIC chief called for increased cooperation among member states and countries outside the region, announcing the group's progress in preparing its own "Water Vision" document and forming an OIC Water Council to address water-related concerns.

"In its first phase, the Water Vision will outline a framework of cooperation on water-related issues in terms of water-sharing experience, capacity development, technology transfer, water governance and institutional reforms," Ihsanoglu said.

He cited the Friendship Dam, to be constructed on the Orontes River at the Turkish-Syrian border, as an excellent example of cooperation and peace among neighboring countries in the field of water.

Charity Ngilu, minister for water and irrigation of Kenya, stressed the importance of water in promoting peace, especially in regions where water scarcity prevails.

"There have been many conflicts caused by water scarcity not only among African countries, but even within regions of the same country," She said, adding Kenya would ask Turkey for cooperation and assistance in water management and other related issues.