GRAND CAYMAN, CAYMAN ISLANDS — (09/10/12 — Tethys Petroleum Limited (“Tethys” or “the Company”) (TSX:TPL) (LSE:TPL) today is pleased to announce the commencement of drilling operations at the AKD07 appraisal/exploration well in Kazakhstan, and the commencement of further seismic acquisition in Tajikistan.

The well is located to the south-east of the producing Doris field and is designed to target a potential downdip field extension at the Cretaceous Aptian sand level in what is believed to be a channel sand system (the “Doris” sand), whilst simultaneously targeting an exciting exploration prospect (named “Dyna”), which has been identified on the 3D seismic data from a bright amplitude anomaly at a slightly shallower level, and is interpreted to be part of a separate, larger sand fan or sheet sand system. This Dyna prospect has 128 million barrels gross mean unrisked recoverable prospective resources attributed to it (Gustavson Associates). The well also has a deeper Jurassic level target as interpreted from the 3D seismic.

The well is forecast to take approximately 55 days to drill to a planned total depth of 2,540 meters using Tethys’ own ZJ70 “Telesto” rig. Following the drilling it is planned to run wireline logs, and, subject to the log results, conduct flow testing operations.

The recently updated prospective resource report for Tethys’ Kazakhstan assets (Gustavson Associates) estimates gross unrisked recoverable mean prospective oil resources of 1.23 billion barrels of oil and this is the first well since that report to target this exploration upside.

In Tajikistan, seismic data acquisition has now commenced as part of the new seismic programme.

The initial analysis of the data from the aerial graviometry survey completed at the end of 2011 along with regional seismic and well data revealed several attractive prospective areas with the potential presence of very large deep sub-salt and sub-thrust prospects within the Bokhtar Production Sharing Contract (“PSC”) Area. The additional seismic now being acquired will target the best of these areas and provide the final data in a comprehensive programme. The programme, up to 870 km of 2D seismic acquisition, is designed to identify a possible drilling location for the first deep well which the Company expects to commence drilling in 2013.

This stage of the seismic programme involves the acquisition of new seismic in two areas; the Vaksh Valley and the Dushanbe Step. The programme has been designed to target these areas as the data have identified them to be the most likely to contain large deep prospects including potential Jurassic reefs located on the edge of likely Permian basement high features. Jurassic reefs form some of the most prolific fields in the Amu Darya basin (of which the Bokhtar PSC, being in the Afghan Tajik basin, forms part) and no wells have ever been drilled through the overlying salt layer into that horizon in this region of Tajikistan to date. The area also has potential in Lower Cretaceous sandstones which form the reservoir in some super-giant fields in Turkmenistan and Uzbekistan. The Amu Darya basin is extremely prolific containing oil, gas and condensate fields and indeed some of the world’s largest gas fields are located in this basin. These data also reveal significant potential in other parts of the PSC Area, including the Kulob area, however it has been decided to initially focus on the Vaksh Valley and the Dushanbe Step.

The recently updated prospective resource report for our Tajikistan assets (Gustavson Associates) estimates gross unrisked recoverable mean prospective resources of 27.5 billion barrels of oil equivalent (114TCF gas and 8.5 billion barrels of oil) within the Tethys PSC acreage which covers an area of 34,785 sq km.

It is expected that this new seismic programme will further confirm the high potential in the Tethys Bokhtar PSC acreage in which Tethys owns an 85% interest. Tethys continues to hold discussions with a number of potential farminees with the aim of concluding an agreement by year-end.

In addition, the planned workover programme on the Beshtentak Field has commenced with wellsite preparation of the first two candidate wells. Results are expected in Q4 2012.

In a separate story concerning Tethys Petroleum the company announced operational changes

GRAND CAYMAN, CAYMAN ISLANDS, Sep 10, 2012  — Tethys Petroleum Limited today announced that Dr. David Robson has been re-appointed as Executive Chairman and President of the Company with Julian Hammond remaining as Chief Executive Officer (“CEO”).

The Company announced on 30th July 2012 that Dr. David Robson, previously Executive Chairman, President and Chief Executive Officer, was unable to continue in his roles due to health reasons, however, Tethys is delighted to announce that Dr. Robson has made an excellent recovery from his illness and is now resuming executive duties with the Company.

At the time of Dr. Robson’s illness, Julian Hammond was appointed Chief Executive Officer and President and the Rt. Hon Peter Lilley M.P. was appointed as Non Executive Chairman. Julian Hammond will continue in the role of Chief Executive Officer and Peter Lilley will resume his role as Vice Chairman and Senior Independent Non-Executive Director.

Julian Hammond, CEO of Tethys, said:

“The Board is delighted that David has made such a speedy recovery from the illness that forced him to stand down from his roles earlier this year. That he is able to return to the Company to resume his duties is a very positive development and I look forward to working with him going forward.”

Dr. David Robson, Executive Chairman and President of Tethys, commented:

“I am extremely pleased to be resuming my duties with the Company and working with Julian and the other members of the senior management team to move Tethys forward successfully. We have a very exciting period coming up with further drilling in Kazakhstan, exploration in Tajikistan and our new field in Uzbekistan and I am looking forward to further success and to delivering value for the stakeholders of Tethys.”

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, 2011 for a description of risks and uncertainties relevant to our business, including our exploration activities (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.