An energy exploration venture has made the largest ever gas field discovery to have been found off Israel, local company Isramco said.
The gas field, 90km off Israel's Mediterranean coast near Haifa, has estimated reserves worth $US15 billion, Isramco said in a statement on Sunday.
Isramco has a 28.9% stake in the venture, the second largest after US oil company Noble Energy's 36% per cent.
The other stakeholders include are Delek Drilling and Avner Oil and Gas Exploration.
Delek's owner Yitzhak Tshuva told army radio the source of "high-quality" natural gas at the field was enough to reduce the cost of energy in Israel by 20%.
Following the announcement, shares in Isramco and Delek jumped more than 30% on the Tel Aviv Stock Exchange.
Egypt is a major supplier of natural gas to Israel under a contract signed in 2005 with EMG, a private Egyptian-Israeli consortium.