Kazakh State Reserves Approved for Doris Oil Discovery

October 25, 2010

ALMATY, KAZAKHSTAN, Oct 25, 2010 (MARKETWIRE via COMTEX) —

Tethys Petroleum Limited (“Tethys” or the “Company”) (TSX: TPL) announced today it had received Kazakh State approved oil reserves for its Doris (AKD01) oil discovery in Kazakhstan.

Tethys’ wholly owned subsidiary TethysAralGas LLP (“TAG”) has received approved oil reserves (in C1 and C2 categories) from the Kazakh State Reserve Committee (part of the State Committee for Geology) for the AKD01 (Doris) oil discovery. This is an important step forward with respect to the approval of TAG’s pilot production project for Doris which is currently under consideration by the Ministry of Oil and Gas with TAG expecting approval of this project by year end.

Tethys also gave a brief update on current operations activities in Kazakhstan.

On the G6RE (Dodone) well preparations are underway for the testing and acidisation (by Schlumberger) of the Upper Jurassic carbonate interval which would be carried out in conjunction with acidisation of the same interval in the AKD02 (Doris NW) well. Testing operations should commence within the next week to ten days with initial results being available in November.

The AKD03 (Dione) exploration well is currently drilling ahead at a depth of 3,304 metres (in what is interpreted to be the lower Jurassic sequence). A further interval with hydrocarbon shows has been encountered whilst drilling through the middle Jurassic sequence at approximately 3,000 metres. This well is planned to penetrate the Triassic sequence and reach total depth of some 4,300 metres in the Permo-Carboniferous. It is currently anticipated that total depth should be reached in mid-November.

Acquisition of the initially planned 290.3 km(2)of 3D seismic has now been completed and the survey has now been extended westwards to include the area around the Dodone prospect. Processing of the data is now underway.

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, including the risks relating to regulatory approvals and of sufficiency of the proceeds for the purposes contemplated. The Kazakh State reserve figures are not deemed to be compliant with NI-51-101 and to date no independent reserve calculation consistent with Canadian regulatory rules has been carried out on Doris.

See the description of risks and uncertainties and underlying factors and assumptions relevant to the offering and “forward looking information” contained herein and to the Company’s business, including its exploration and development activities, contained in the Annual Information Form dated March 31, 2010 and other corporate filings (which are incorporated herein by reference). The “forward looking statements” contained herein speak only as of the date of this press release and, unless required by applicable law, the Company undertakes no obligation to publicly update or revise such information, whether as a result of new information, future events or otherwise.

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

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