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Exhibit 10.3
 

 

       
            Kerr-McGee North Sea (U.K.) Limited
            Ninian House
            Crawpell Road
            Altens
            Aberdeen AB12 3LG.

30th August 2005

Centrica Resources Limited
Millstream East
Maidenhead Road
Windsor
Berkshire SL4 5GD.

Dear Sirs
 
We refer to the sale and purchase agreement executed on 6th August 2005 between
Kerr-McGee North Sea (U.K.) Limited (“Kerr-McGee”) and Centrica Resources
Limited (“Centrica”) in respect of Kerr-McGee’s interests in the Buckland Field
(the “Buckland SPA”) and the sale and purchase agreement executed on 6th August
2005 between Kerr-McGee North Sea (U.K.) Limited and Centrica Resources Limited
in respect of Kerr-McGee’s interests in the Skene Field (the “Skene SPA”).
 
In order to more clearly reflect the intention of the parties we agree that
 
(1) with effect from 6th August 2005 the text of Schedule 7 to the Buckland SPA
shall be deleted and replaced with the following text:
 
Buckland Field
 
The following interests held by Kerr-McGee North Sea (U.K.) Limited:
 
Kerr-McGee’s thirty three decimal three three three three three three three
percent (33.3333333%) interest in UKCS Licence P.103 Area G and Area W, as Areas
G and W are defined in the Restated Northern Waters Joint Operating Agreement
dated 9th November 1995 as amended.
 
(2) with effect from 6th August 2005 the text of Schedule 7 to the Skene SPA
shall be deleted and replaced with the following text:
 
Skene Field
 
The following interest held by Kerr-McGee North Sea (U.K.) Limited:
 
 
 

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Kerr-McGee’s thirty three decimal three three three three three three three
percent (33.3333333%) interest in UKCS Licence P.103 Area O, as Area O is
defined in the Restated Northern Waters Joint Operating Agreement dated 9th
November 1995 as amended.
 
(3) in respect of the Buckland SPA, the Base Consideration as therein defined
shall be allocated by Centrica between Areas G and W and a notice, supplemental
to that served on the Area G parties and the Area W parties on 10th August 2005,
shall be served by Kerr-McGee on the Area G parties and the Area W parties
stating such allocated consideration.
 
Please sign and return the enclosed copy of this letter indicating your
agreement to it.
 
Yours faithfully
 
TERENCE JUPP
 

 
Kerr McGee North Sea (UK) Limited
 
ANTHONY C. HENSHAW
 

 
Agreed for Centrica Resources Limited