A border dispute off the coasts of Lebanon and Israel threatens another violent conflict in the Middle East, as the two countries battle over a zone that has the potential to produce billions of dollars in energy revenue.

The dispute, which has defied U.S. efforts at mediation, is the result of Israeli and Lebanese claims over a potentially lucrative plot of territory in the Mediterranean Sea. The 850 square kilometers in the triangle-shaped area, which both countries consider to be their Exclusive Economic Zone, could be full of offshore natural gas and oil.