Holding(s) in Company

For filings with the FSA include the annex

For filings with issuer exclude the annex 

TR-1: Notifications of Major Interests in Shares

1. Identity of the issuer or the underlying issuer of existing shares to which voting rights are attached:

Premier Oil plc

2. Reason for notification (yes/no)

An acquisition or disposal of voting rights

Yes

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

No

An event changing the breakdown of voting rights

No

Other (please specify):___________________________

No

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

Ameriprise Financial, Inc. and its group

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

See additional information under 13.

5. Date of transaction (and date on which the threshold is crossed or reached if different):

19 March 2009

6. Date on which issuer notified:

20 March 2009

7. Threshold(s) that is/are crossed or reached:

Above the threshold of 5%

8: Notified Details

A: Voting rights attached to shares

Class/type of shares

If possible use ISIN code

Situation previous to the triggering transaction

Resulting situation after the triggering transaction

Number of shares

Number of voting rights

Number of shares

Number of voting rights

Percentage of voting rights

Direct

Indirect

Direct

Indirect

B: Financial Instruments

Resulting situation after the triggering transaction

Type of financial instrument

Expiration date

Exercise/ conversion period/date 

No. of voting rights that may be acquired (if the instrument exercised/converted)

Percentage of voting rights

Total (A+B)

Number of voting rights

Percentage of voting rights

4,028,672

5.076%

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

Ameriprise Financial, Inc., which controls the voting rights of Threadneedle Asset Management Holdings Ltd, which controls the voting rights of Threadneedle Asset Management Ltd, Threadneedle International Ltd and Threadneedle Pensions Ltd.

Proxy Voting:

10. Name of proxy holder:

N/A

11. Number of voting rights proxy holder will cease to hold:

N/A

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

N/A

13. Additional information:

Registered Owner

14 Contact name:

H Garratt, Deputy Company Secretary 

15. Contact telephone name:

+44 (0)20 7730 1111