The current round of Palestinian–Israeli negotiations should confront the region's water conflict described in Haim Watzman's book review (Nature 466, 820; 2010). The conflict has persisted in a covert form since the 1995 Oslo II Agreement; to right the agreement's wrongs, water must be distributed according to fair and legal principles.

Central to the present conflict is the fact that Oslo II sealed the inequitable distribution and control of the transboundary River Jordan and groundwater flows. Nine out of every ten drops of water that fall on the border are currently under Israeli control. International water law would see this change to a roughly 60:40 split in Israel's favour.

Another source of conflict is the Joint Water Committee, set up under Oslo II (J. Selby Rev. Int. Stud. 29, 121–138; 2003). By creating a bargaining market, it has stifled investment in and management of the Palestinian water sector (see http://go.nature.com/gxdPWB).

For example, Israeli approval of Palestinian water projects is contingent on Palestinian approval of projects for the encroaching illegal settlements. When such projects are refused by the Palestinian side, the Israeli side denies internationally sponsored development projects destined for Palestinian towns. The Palestinian Water Authority's credibility is eroded with each settlement it legitimizes, and anger mounts as violations pile up (see http://go.nature.com/714REE).

Establishing a more effective joint committee is best done using a new agreement that ensures fair allocations. The basis for resolving the conflict could come from Israel's desalination plants and from reallocating water away from its exported water-intensive commodities, both of which would relieve pressure on freshwater supplies.

Negotiators and mediators who fail to push for this makeover will be perpetuating, not resolving, the water conflict.