Tajik Exploration Well Finds Oil

May 27, 2011

DUSHANBE, TAJIKISTAN, May 27, 2011 (MARKETWIRE via COMTEX) —

Tethys Petroleum Limited (“Tethys” or the “Company”) (TSX: TPL) today issued a holding statement with regard to oil being encountered in its Tajik exploration well East Olimtoi EOL09 in order to ensure all pertinent information is available to the market and the Company’s stakeholders.

While drilling at a depth of 3,342 metres in sandstones of the Alai formation (a secondary target) there was a strong flow of live oil to the surface accompanied by 33% gas in the drilling mud. After closing of the blowout preventer the well was successfully stabilised and drilling operations have now recommenced.

The oil, which appears to be of medium density, flowed despite drilling with heavy mud (1.57 SG) reflecting a pressure of some 512 atmospheres (7,524 psia) in the reservoir.

The primary target for the well is the Paleogene Bukhara limestone formation and it is planned to set casing prior to entering this zone. The well is exploring an attractive salt induced structure and is planned to reach a total depth of some 3,800 metres.

The well is located in the south-east of Tethys’ Contract area, south of the town of Kulob and only some 10 kilometres north-west of the Afghan border. The nearest oilfield in that region is the Beshtentak field some 75 km to the north-west which produces oil from the Bukhara limestone.

This press release is an interim release and readers should note that the interval, which produced oil, has not been fully evaluated either with wireline logs or production testing. As such there is no guarantee that this zone will produce commercial hydrocarbons when properly tested but the observed oil flow is obviously a positive indication.

Tethys is focused on oil and gas exploration and production activities in Central Asia with activities currently in the Republics of Kazakhstan, Tajikistan and Uzbekistan. 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, 2010 for a description of risks and uncertainties relevant to our business, including our exploration activities.

Contacts: Tethys Petroleum Limited Sabin Rossi Vice President Investor Relations +1 416 572 2065 +1 416 572 2201 (FAX) Tethys Petroleum Limited info@tethyspetroleum.com www.tethyspetroleum.com Mobile site: http://m.tethyspetroleum.com In Asia-Pacific Quam IR Anita Wan, Associate Director + (852) 2217-2999 + (852) 2217-2999 (FAX) anita.wan@quamgroup.com
SOURCE: Tethys Petroleum Limited

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