A report for the Swiss and Swedish governments warned on Thursday that water shortages in the Middle East were so alarming that opposing camps in the region would have little choice but to cooperate.

Swiss Foreign Minister Micheline Calmy-Rey called for closer cooperation between Turkey, Iraq, Syria, Lebanon, Jordan, the Palestinians and Israel on managing increasingly scarce water resources, arguing that water could also be used to forge a "blue peace."

"The report comes to an alarming conclusion; five of the seven countries are experiencing a structural shortage and debit of most of the big rivers has declined by 50 to 90 percent between 1960," she told journalists.

"In the future the main geopolitical resource in the Middle East will be water more than oil," she added, warning that it was closely tied to peace efforts.

The report by an Indian thinktank, Strategic Foresight Group, highlighted huge depletion of major rivers such as the Jordan and Yarmouk in the past half a century, the punctual depletion of the Euphrates by drought and the shrinkage of the Dead Sea to a small lake by 2050.

However, the report also acknowledged the difference between the countries, with upstream Turkey in a position to "influence prospects of peace" despite the collapse of 1980s plan to pipe water to Israel and Gulf states.

Downstream territories such as Israel, Jordan and Palestinian territories were in the worst position with mounting clean water deficits of up to 500-700 million cubic metres each.

The report also argued that technical solutions such as desalination or wastewater recycling in Israel would ultimately have limited scope.

"Purely unilateral solutions will mainly work for a decade or so but Israel will have to look for external sources and regional cooperation beyond 2020 to ensure its water security," it said.

Swiss diplomats said they had already started to lobby the seven governments for a joint water cooperation council expanding on an nascent Turkish, Iraqi, Jordanian and Syrian effort, as well as other steps, even if they admitted that it would be challenging.