Start of Drilling of Second Hassi Ba Hamou Well

Sonatrach and partners BG Group and Gulf Keystone Petroleum announced the following operational update in respect of the Hassi Ba Hamou Perimeter, which covers 18,380 km2 in the Allal Dome of Central Algeria.

The HBHN-1 exploration well which is the second well to be drilled of a six well commitment on the HBH Permit was spudded on 21st February 2008. Three appraisal and three exploration wells are to be drilled back to back in the first exploration phase of the licence which expires in September 2008.

Licensees of the HBH Permit are Gulf Keystone 38.25%, BG Group 36.75% and Sonatrach 25%. Gulf Keystone farmed out 36.75% of the HBH Permit to BG Group effective December 2006.