Drilling Update

October 27, 2009

ST. PETER PORT, GUERNSEY, Oct 27, 2009 (MARKETWIRE via COMTEX) — Tethys Petroleum Limited (“Tethys” or the “Company”) (TSX: TPL) today provided an update on its drilling activities in Central Asia.

Kazakhstan

Exploration well AKD01, which is the Company’s first “deep” well in the Akkulka Block (“Akkulka”) in Kazakhstan, reached a total depth of 3,414 m (11,200 ft) in what is interpreted to be the Triassic sequence. This well had targets in the Cretaceous/ Jurassic sequence and in the underlying Triassic sequence.

As previously reported, based on the electric logs, independent petrophysical analysis confirmed the interpretation of moveable hydrocarbons in at least two zones in the Lower Cretaceous / Jurassic interval which may be oil and/or gas condensate. In order not to jeopardise these zones the well was plugged back and a testing program initiated on two zones, one at approximately 2,350 m (7,708 ft) and the other at approximately 2,160 m (7,085 ft). The lower zone is interpreted to be a dolomitic interval which is believed to be regionally extensive, whilst the upper zone is interpreted to be a good quality sandstone. Production testing of the lower zone has now commenced and the well has flowed light oil/condensate to surface but the well is not yet cleaned up and no accurate flow rate is yet available. A sample of the liquid hydrocarbon has been sent to a laboratory for further tests and Tethys is continuing with the testing program with further results on this lower zone being expected in the next few weeks. Although the recovery of liquid hydrocarbons from the well is encouraging only after production testing can a definitive statement be made on the potential for commercial production of oil and/or gas from this well.

Once the lower zone has been fully tested the upper zone will then be perforated and tested, which is expected to take place in approximately four weeks time.

Tajikistan

Operations continue on the East Komsomolsk well KOM200 where drilling conditions have been challenging. After encountering a significant gas influx whilst drilling the upper section of this well operations were focused on stabilising the well and controlling the gas in the upper section. This was achieved successfully and the well is currently in the first prognosed reservoir zone (the Cenomanian sequence), which is a secondary target, where a further significant gas influx occurred with up to 78% methane being observed at surface. The well is currently being conditioned prior to drilling ahead from the current depth of 1,020 m (3,346 ft).

East Olimtoi exploration well EOL09 is currently at its next planned casing point at a depth of 2,910 m (9,547 ft). This well is being drilled in the south east part of the Bokhtar PSC area, south of Kulob and just to the north of the Panj river.

Uzbekistan

The location for the next North Urtabulak field development well, NUR116 has now been selected within the relatively undrilled “NW salt zone” of the field. Contract negotiations are being finalised with Xibu Drilling Engineering Company Limited (part of Great Wall Drilling Company) to commence drilling of this well on a turnkey basis. The site is being prepared and drilling is expected to commence once the rig, which is already at the field, is erected.

North Urtabulak was the second largest oilfield in Uzbekistan and Tethys believes there is substantially more recoverable oil remaining. It is expected that the new well will be put on production immediately it is completed.

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 fact that the interim drilling results reported in this press release are not necessarily indicative of the final drilling results once drilling of the relevant wells has been completed.” See our Annual Information Form for the year ended December 31, 2008 and the following paragraph for a description of risks and uncertainties relevant to our business, including our exploration and development activities.

There are numerous uncertainties inherent in estimated resources, including many factors beyond the Company’s control, and no assurance can be given that the indicated levels of resources or recovery of natural gas can crude oil will be realized. In general, estimates of recoverable natural gas and crude oil resources are based upon a number of factors and assumptions made as of the date on which resource estimates were determined, such as geological and engineering estimates which have inherent uncertainties and the assumed effect of regulation by governmental agencies and estimates of future commodity prices and operating costs, all of which may vary considerably from actual results. All such estimates are, to some degree, uncertain and classifications of resources are only attempts to define the degree of uncertainty involved. For these reasons, estimates of the recoverable natural gas and crude oil and the classification of such resources based on risk of recovery, prepared by different engineers or by the same engineers at different times, may vary substantially. There is no certainty that any portion of the resources will be discovered. If discovered, there is no certainty that it will be commercially viable to produce any portion of the resources.

The interpretation of logs to indicate the possible presence of hydrocarbons does not mean that these hydrocarbons are definitely present and if they are present it does not mean these hydrocarbons can be produced in commercial quantities.

Contacts:
Tethys Petroleum Limited
Sabin Rossi
Vice President Investor Relations
Office: +1 416 572 2065
+1 416 572 2201 (FAX)
info@tethyspetroleum.com
www.tethyspetroleum.com

In Kazakhstan
PG Communications
Ardak Akanov, Managing Director
Office phone/fax: +7 (727) 272 8867
development@pressclub.kz

In Asia-Pacific
Quam IR
Anita Wan
Associate Director
Office phone/fax: + (852) 2217-2999
anita.wan@quamgroup.com

SOURCE: Tethys Petroleum Limited

mailto:info@tethyspetroleum.com
http://www.tethyspetroleum.com
mailto:development@pressclub.kz
mailto:anita.wan@quamgroup.com