2008-05-16

Gas Tested on First Kul-Bas Exploration Well

Friday, May 16, 2008 – Bozoi, Kazakhstan – Tethys Petroleum Limited (“Tethys” or the “Company”) (TSX: TPL) today announced the initial results of its KUL01 exploration well, the first exploration well the Company has drilled on its 8,658 km2 (2.14 million acre) Kul-Bas exploration block.

Well KUL01 is located 8.6 km (5.3 miles) to the south west of Bozoi village and to the north of the tie in point of the company’s producing Kyzyloi gas field to the Bukhara-Urals trunkline system. The well was drilled to a total depth of 593 metres (1,945 feet) and targeting the shallow gas sands equivalent to the Kyzyloi sand units and potential deeper targets. The Kyzyloi Sand was encountered at a depth of 358 metres (1,175 feet), approximately 100 metres (328 feet) shallower than the Company’s Kyzyloi Field), and the deeper Tasaran Sand unit at 448 metres (1,470 feet). A net interval of 3 metres (10 feet) was perforated and tested in the Kyzyloi Sand, the sand showing high porosity of some 35%. The well was tested on various choke sizes up to 30 mm (76/64”) but at larger chokes limited sand production lead to unreliable data. The largest choke on which reliable data was obtained was a 16 mm (40/64”) choke where gas flowed at a rate of approximately 54 thousand cubic metres per day (Mcm/d) (2 million cubic feet per day (MMcf/d)). The test showed no signs of depletion. The Absolute Open Hole (“AOH”) flow potential for the test interval has been calculated independently based on these data at 91 Mcm/d (3.2 MMcf/d). Although elevated gas levels were observed in the Tasaran during drilling, and wireline logs showed some gas saturations, gas did not flow under test.

Graham Wall, Vice President Technical of Tethys, commented, “We are pleased to have tested gas on our first exploration well on the Kul-Bas block. The shallow depth and more unconsolidated nature of the Kyzyloi Sand in this gas accumulation will potentially result in the need for sand screens or similar for production. This prospect was previously mapped as extending below the Bukhara-Urals gas trunkline and we are now evaluating the optimal scheme for the development of this new discovery. Meanwhile we continue to map the deeper Tasaran units and their potential in this area with the data from this well providing additional information. ”

Tethys is focused on oil and gas exploration and production activities in Central Asia with activities currently in the Republic of Kazakhstan and more recently the Republic of Tajikistan. This highly prolific oil and gas area is rapidly developing and Tethys believes that significant potential exists in both exploration and in discovered deposits.

This press release contains “forward-looking information” which may include, but is not limited to, statements with respect to our operations. Such forward looking statements reflect our current views with respect to future events and are subject to certain risks, uncertainties and assumptions. See our Annual Information Form for the year ended December 31, 2007 for a description of risks and uncertainties relevant to our business, including our exploration activities.

For more information please contact:

Sabin Rossi
Vice President Investor Relations Tethys Petroleum Limited
TD Canada Trust Tower
161 Bay Street, 27th Floor
Toronto N5J 2S1
Canada

Office: 1-416-572-2065
Fax: 1-416-572-2201
Cell: 1-617-669-1841
e-mail: info@tethys.gg
website: www.tethyspetroleum.com

In Kazakhstan

Ardak Akanov
Managing Director
PG Communications
Almaty, Samal 2 Business Center Satty

Office phone/fax: 2 72 88 67, 2 72 82 37, 2 72 77 45
Cell: +77017115604
Email: development@pressclub.kz