Conglomerate investment company Israel Corp. Ltd. (ILCO.TV) has signed a deal to buy $4 billion in natural gas from the local offshore Tamar field, becoming that field's biggest potential customer after the state-owned electric company.

Israel Corp., through three of its subsidiaries, will buy several billion cubic meters of natural gas over about 15 years, Delek Drilling Ltd. Partnership (DEDRL.TV), one of the partners in Tamar, said Monday.

This deal comes after a 2010 deal in which Israel Corp. selected an Egyptian gas supply contract over one from Tamar. But that contract, signed with East Mediterranean Gas Co., was never actually fulfilled because last year EMG stopped supplying gas to Israeli companies after the fall of former Egyptian president Hosni Mubarak's regime and a subsequent series of attacks on the pipeline in the
Sinai Peninsula .

Israel 's state-owned Israel Electric Corp. recently signed a deal to buy $20 billion in natural gas from Tamar over the next two decades. Tamar is scheduled to begin production next year, and contains an estimated 9 trillion cubic feet of natural gas.

Power companies, government officials and investors are eager for the supply from Tamar to start because
Israel is currently suffering from a natural gas shortage after EMG stopped supplying gas to the country, which has pushed up electricity prices.

The Israel Corp. subsidiaries involved in the gas supply deal are Rotem OPC Ltd., a private power plant company, Israel Chemicals Ltd. (ICL.TV), and Oil Refineries Ltd. (ORL.TV).

Stakeholders in Tamar include Delek Drilling and Avner, both subsidiaries of Delek Group Ltd., which each hold a 15.6% stake; Isramco 2 Negev Ltd. Partnership (ISRAL.TV), which holds 28%; and Houston-based Noble Energy Inc. (NBL.NYSE), which holds 36%.

At 0803 GMT, shares of Israel Corp. were up 15 shekels ($3.88), or 0.61%, at ILS2,473.00, in a lower Tel Aviv market. Trading in shares of the Israel Corp. subsidiaries involved in the deal, and shares of the Tamar stakeholders, had been halted due to the announcement of the deal.