Holding(s) in Company

TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARES

1. Identity of the issuer or the underlying issuerof existing shares to which voting rights areattached: ii

Lansdowne Oil & Gas plc

2 Reason for the notification (please tick the appropriate box or boxes):

An acquisition or disposal of voting rights

√

An acquisition or disposal of qualifying financial instruments which may result in the acquisition of shares already issued to which voting rights are attached

An acquisition or disposal of instruments with similar economic effect to qualifying financial instruments

An event changing the breakdown of voting rights

Other (please specify):

3. Full name of person(s) subject to thenotification obligation: iii

Aviva plc & its subsidiaries

4. Full name of shareholder(s)  (if different from 3.):iv

Registered Holder:

BNY (Nominees) Limited 75,482*

BNY Norwich Union Nominees Limited 1,365,906*

Chase (GA Group) Nominees Limited 7,749,994*

Chase Nominees Limited 201,655*

Vidacos Nominees Limited 55,638*

*denotes direct interest

Chase Nominees Limited  171,325

5. Date of the transaction and date onwhich the threshold is crossed orreached: v

23 August 2012

6. Date on which issuer notified:

24 August 2012

7. Threshold(s) that is/are crossed orreached: vi, vii

5% Change at Combined Interest Level

8. Notified details:

A: Voting rights attached to shares viii, ix

Class/type ofshares

if possible usingthe ISIN CODE

Situation previousto the triggeringtransaction

Resulting situation after the triggering transaction

NumberofShares

NumberofVotingRights

Numberof shares

Number of votingrights

% of voting rights x

Direct

Direct xi

Indirect xii

Direct

Indirect

Ordinary Shares

GB00B1250X28

Not Disclosable

Not Disclosable

9,620,000

9,448,675

171,325

7.72%

0.14%

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financialinstrument

Expirationdate xiii

Exercise/Conversion Period xiv

Number of votingrights that may beacquired if theinstrument isexercised/ converted.

% of votingrights

C: Financial Instruments with similar economic effect to Qualifying Financial Instruments xv, xvi

Resulting situation after the triggering transaction

Type of financialinstrument

Exercise price

Expiration date xvii

Exercise/Conversion period xviii

Number of voting rights instrument refers to

% of voting rights xix, xx

Nominal

Delta

Total (A+B+C)

Number of voting rights

Percentage of voting rights

9,620,000

7.86%

9. Chain of controlled undertakings through which the voting rights and/or thefinancial instruments are effectively held, if applicable: xxi

The voting rights are managed and controlled by Aviva Investors Global Services Limited, with the following chain of controlled undertakings:-

Aviva Investors Global Services Limited:

·; Aviva plc (Parent Company)

·; Aviva Group Holdings Limited (wholly owned subsidiary of Aviva plc)

·; Aviva Investors Holdings Limited (wholly owned subsidiary of Aviva Group Holdings Limited)

·; Aviva Investors Global Services Limited (wholly owned subsidiary of Aviva Investors Holdings Limited)

Proxy Voting:

10. Name of the proxy holder:

See Section 4

11. Number of voting rights proxy holder will ceaseto hold:

12. Date on which proxy holder will cease to holdvoting rights:

13. Additional information:

Figures are based on a total number of voting rights of 122,358,159 as per the Company's Total Voting Rights Announcement of 26 July 2011.

14. Contact name:

Chris Moar

15. Contact telephone number:

01224 748489