Tullow Makes Gas Discovery with Monroe Well in the North Sea

Tullow Oil has made a gas discovery with the "Monroe" exploration well, 44/17b-7.

The 44/17b-7 discovery, located within Tullow's Caister Murdoch System ("CMS") core area, was spudded on February by Noble Drilling's jackup, Noble Julie Robertson, and reached a depth of 12,611ft. The well encountered gas-bearing Carboniferous reservoir sands and has been suspended as a potential future producer.

Subject to the outcome of pre-development studies, it is the co-venturers' plan to re-enter this well and tie it back to the ConcocoPhillips operated CMS III production network. First production is expected by mid-2005.

Co-venturers in the discovery are Tullow Oil UK (15% interest), GDF Britain Ltd (39% interest and Operator) and ConocoPhillips (UK) Limited (46% interest).

Aidan Heavey, Tullow's Chief Executive commented:

"The success of the Monroe well demonstrates the continued prospectivity of this core area and paves the way for the next phase of development of CMS. We look forward to further active exploration and development activities on this exciting trend"