Annual Information Update

April 20, 2012

LONDON, ENGLAND--(Marketwire - April 20, 2012) - Tethys Petroleum (TSX:TPL)(LSE:TPL) today provided an Annual Information Update for the period 25 July 2011 to 19 April 2012.

In accordance with Prospectus Rule 5.2, the Company sets out below a summary of the information, which has been published or made available to the public during the period. The period is less than a full year as the Company's secondary listing onto the London Stock exchange commenced 25 July 2011. The information referred to in this update was current at the time of publication, but some information may now be out of date and some of it will have been prepared in accordance with requirements of jurisdictions other than England & Wales. It is not provided for any other purpose and neither the Company, nor any other person, takes any responsibility for, or makes any representation, express or implied, as to the accuracy or completeness of, the information, which it contains. Further, such information prepared in accordance with the laws or regulations of a particular jurisdiction other than England & Wales may not comply with or meet the relevant standards of disclosure in any other jurisdiction.

1. The following announcements were made during the period to the London Stock Exchange via RNS:

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25/07/11 Tethys Petroleum Lists on London Stock Exchange
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26/07/11 AKD05 Well Flows at over 2,000 barrels per day
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08/08/11 Opening of Kazakhstan Oil Production Facilities
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15/08//11 Q2 Results and Conference Call Details
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15/08/11 Operational Update
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05/09/11 Afghan Bid Update
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07/09/11 Kazakhstan KBD01 (Kalypso) Exploration Well Update
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12/09/11 Tajikistan Operations Update
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26/09/11 Doris AKD06 Well Initial Results
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20/10/11 Tajikistan-Beshtentak Well Flows Over 500 Barrels of Oil per
Day
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14/11/11 Third Quarter 2011 Financial Results and Operational Update
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15/11/11 Kazakh AKD06 Well Flows Over 4,300 Barrels of Oil Per Day
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18/11/11 Uzbekistan MOU Signed
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22/11/11 Price Monitoring Extension
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29/11/11 Tethys Announces USD$13 Million Private Placement
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02/12/11 Tajikistan Update
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09/12/11 Tethys Announces Completion of US$13 Million Private
Placement
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12/12/11 Tethys Total Voting Rights
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13/12/11 Tethys completes Tajikistan Acquisition
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19/12/11 Tajikistan Persea 1 Well Initial Results
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30/12/11 Kazakhstan Oil Transportation Update
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09/01/12 Tajikistan Update
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18/01/12 New Director Appointed
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30/01/12 Aral Oil Terminal Inaugurated
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01/02/12 Uzbekistan Exploration MOU Signed
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09/02/12 Tajik Seismic Tender Announced
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21/03/12 2011 Reserves Report
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30/03/12 2011 Year End Results
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12/04/12 Announcement to Block Listing
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13/04/12 First Oil Sales Through Kazakh Oil Terminal
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16/04/12 Appointment of Corporate Brokers
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19/04/12 Tethys Receives Extension for Akkulka Exploration Contract
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The above documents are available on the Company's website at: 

http://www.tethyspetroleum.com/tethys/irindex.action

The following documents were submitted to the National Storage Mechanism and can be found here 

http://www.morningstar.co.uk/uk/NSM

The Annual Report for the period ended date 31 December 2011, which was submitted to the National Storage Mechanism on
30 March 2012 is available on the Company's website at: 

http://www.tethyspetroleum.com/tethys/announReports.action

The Financial Statements and Management's Analysis and Discussion for the period ended date 31 December 2011, which was submitted to the National Storage Mechanism on 30 March 2012, is available on the Company's website at:

http://www.tethyspetroleum.com/tethys/announReports.action

The Prospectus was submitted to the National Storage Mechanism on 21 July 2011, is available on the Company's website at: 

http://www.tethyspetroleum.com/tethys/irwebcasting.action

2. The following announcements were made during the period to the Toronto Stock Exchange via SEDAR.

Announcements made during the period were:

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25/07/11 Tethys Petroleum Lists on London Stock Exchange
----------------------------------------------------------------------------
26/07/11 AKD05 Well Flows at over 2,000 barrels per day
----------------------------------------------------------------------------
08/08/11 Opening of Kazakhstan Oil Production Facilities
----------------------------------------------------------------------------
15/08/11 Q2 Results and Conference Call Details
----------------------------------------------------------------------------
15/08/11 Operational Update
----------------------------------------------------------------------------
05/09/11 Afghan Bid Update
----------------------------------------------------------------------------
07/09/11 Kazakhstan KBD01 (Kalypso) Exploration Well Update
----------------------------------------------------------------------------
12/09/11 Tajikistan Operations Update
----------------------------------------------------------------------------
26/09/11 Doris AKD06 Well Initial Results
----------------------------------------------------------------------------
20/10/11 Tajikistan-Beshtentak Well Flows Over 500 Barrels of Oil per
Day
----------------------------------------------------------------------------
14/11/11 Third Quarter 2011 Financial Results and Operational Update
----------------------------------------------------------------------------
15/11/11 Kazakh AKD06 Well Flows Over 4,300 Barrels of Oil Per Day
----------------------------------------------------------------------------
18/11/11 Uzbekistan MOU Signed
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29/11/11 Tethys Announces USD$13 Million Private Placement
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02/12/11 Tajikistan Update
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09/12/11 Tethys Announces Completion of US$13 Million Private Placement
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13/12/11 Tethys completes Tajikistan Acquisition
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19/12/11 Tajikistan Persea 1 Well Initial Results
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30/12/11 Kazakhstan Oil Transportation Update
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09/01/12 Tajikistan Update
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18/01/12 New Director Appointed
----------------------------------------------------------------------------
30/01/12 Aral Oil Terminal Inaugurated
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01/02/12 Uzbekistan Exploration MOU Signed
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09/02/12 Tajik Seismic Tender Announced
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21/03/12 2011 Reserves Report
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30/03/12 2011 Year End Results
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13/04/12 First Oil Sales Through Kazakh Oil Terminal
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16/04/12 Appointment of Corporate Brokers
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19/04/12 Tethys Receives Extension for Akkulka Exploration Contract
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The above documents are available at: http://www.sedar.com/

2.1 The following filings were made during the period onto SEDAR:

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15/08/11 Interim financial statements/report
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15/08/11 MD&A
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15/08/11 52-109F2 - Certification of interim filings - CFO
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15/08/11 52-109F2 - Certification of interim filings - CEO
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14/11/11 Interim financial statements/report
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14/11/11 MD&A
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14/11/11 52-109F2 - Certification of interim filings - CFO
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14/11/11 52-109F2 - Certification of interim filings - CEO
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09/12/11 51-102F3 Material Change Report
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12/12/11 Total Voting Rights
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16/12/11 Material Document(s)
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22/03/12 Material Change Report
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30/03/12 Form 13-502F3C Class 3C Reporting Issuers - Participation Fee
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30/03/12 Audited Annual Financial Information
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30/03/12 MD&A
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30/03/12 Annual Information Form, date ended 31 December 2011
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30/03/12 Notice of filing of 51-101 F1 Information (Form 51-101 F4)
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30/03/12 52-109F1 - Certification of annual filings - CFO
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30/03/12 52-109F1 - Certification of annual filings - CEO
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30/03/12 Notice of meeting and record date
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The above documents are available on the Company's website at:

http://www.tethyspetroleum.com/tethys/announReports.action

3. Announcements which were made during the period to the Kazakhstan Stock Exchange can be located here:

http://www.kase.kz/en/emitters/show/GG_TPL_#section-7

Notes to Editors

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.

FOR FURTHER INFORMATION PLEASE CONTACT:

Tethys Petroleum Limited: North America  
Sabin Rossi  
Vice President Investor Relations  
Office: +1 416-941-1257  
+1 416-947-0167 (FAX)  

OR

Tethys Petroleum Limited: Europe  
Veronica Zhuvaghena  
Vice President Corporate Communications  
Office: +44 1481 725911  
+44 1481 725922 (FAX)  

OR

Corporate Brokers:  
FirstEnergy  
Hugh Sanderson / Derek Smith  
Office: + 44 207 448 0200  

OR

Seymour Pierce  
Richard Redmayne / Jonathan Wright / Stewart Dickson  
Office: +44 207 107 8000  

OR

Asia Pacific: Quam IR  
Anita Wan  
Office phone/fax: +852 2217 2999  

OR

FTI Consulting  
Ben Brewerton / Edward Westropp  
Office: +44 207 831 3113  

OR

Tethys Petroleum Limited  
info@tethyspetroleum.com  
Web: http://www.tethyspetroleum.com  
Mobile site: m.tethyspetroleum.com