CAIRO, Feb 15 (Reuters) - Italy's Eni has invested $4 billion in the development of the first phase of Egypt's giant offshore Mediterranean gas field, Zohr, including the drilling of four wells, an Egyptian official said on Monday.

Eni's total investment in Zohr is between $12 billion and $16 billion, the official added on the sidelines of an Egyptian energy conference.

(Reporting by Ehab Farouk; Writing by Ahmed Aboulenein; Editing by David Goodman) ((ahmed.aboulenein@thomsonreuters.com; +20 2 2394 8097; Reuters Messaging: ahmed.aboulenein.thomsonreuters.com@reuters.net))