Israeli businessman Yitzhak Tshuva is continuing to increase his holdings in oil exploration group Tethys Sea. TheMarker.com has learned that Delek Investments & Properties last week acquired 2% of oil company Avner Oil & Gas's participation units, worth NIS 14.4 million. Most of the units were acquired from a private investor in a large off-the-floor deal. A smaller number of units were acquired during trade.

This time it was Delek Investments and not Delek Energy Systems (which has a 36% holding in Avner), which effected the acquisition, mainly because Delek Investments has greater fluidity reserves than Delek Energy.

Following the acquisition, the Delek group's holdings in Avner come to 40%. Delek also owns a 50% stake in Avner's management company, the other 50% is held by Cohen Development & Industrial Buildings, which trades on the Tel Aviv Stock Exchange. Avner's stock is valued at $187 million.

During the past year, Delek Energy increased its holdings in Avner from 24% to 36% today. It is believed that Delek wants to obtain at least a 50% holding in the future. Avner's stake in Tethys Sea comes to 25.5%, and Avner's partner Delek Drilling has a similar stake. Delek Drilling is controlled directly by Delek Energy. Tethys' remaining equity is held by the American company, the Samedan Oil Corporation.

Last week, the Israel Electric Corporation for the first time announced its intention to enter serious negotiations with Tethys Sea, in order to secure an agreement to acquire half of its gas needs for the coming 10 years from the firm. Tethys Sea is expected to provide the IEC with gas worth an estimated $1.5 billion.