##### 



Exhibit 4.8(b)   EXECUTION COPY




---



##### 



THIS AMENDMENT AGREEMENT Amendment Agreement
 AMONG:
 (1)
    
    ENDEAVOUR INTERNATIONAL HOLDING B.V.a private limited liability company formed under the laws of the
Netherlands (the Borrower);(2)
    
    the GUARANTORSparty hereto; and(3)
    
    CREDIT SUISSE, as Administrative Agent.
 WHEREAS:
 (A)
    
    The parties to this Amendment Agreement entered into the Second Lien Credit and Guarantee Agreement (the
Second Lien Agreement) dated as of October 31, 2006 for the provision of a term loan facility of up
to US$75,000,000.(B)
    
    At the request of the Borrower, the Administrative Agent, with the consent of the Majority Lenders in
accordance with Section 13.02(b) of the Second Lien Agreement, has agreed to make certain amendments to
the Second Lien Agreement upon the terms set out in this Amendment Agreement.
 THE PARTIES AGREE AS FOLLOWS:
 1.
    
    Terms defined in the Second Lien Agreement shall, save to the extent that the context otherwise
requires, bear the same meaning in this Amendment Agreement and in addition Effective Date shall with
respect to this Amendment Agreement have the meaning given to that term in clause 12 below.2.
    
    With effect from the Effective Date, the Second Lien Agreement shall be amended as set out in clauses 3,
4, 5, 6, 7, 8, 9, 10 and 11 below.3.
    
    The following definitions shall be inserted:
 (a)
    
    ICE means the IntercontinentalExchange (or its successor).(b)
    
    Heren means the Heren Monthly Index (or its successor).(c)
    
    Special Acquisition Expenses means any extraordinary, non-recurring expenses relating to the
Acquisition which were incurred in the fiscal quarter ending December 31, 2006.
 4.
    
    The definition of Debt in the Second Lien Agreement shall be amended by inserting the following words
; provided, however, that in the case of any application of the term Debt in determining Total Debt
or Total Secured Debt for purposes of calculating the Reserve Secured Debt Coverage Ratio, the
Reserve Total Debt Coverage Ratio, or the Total Leverage Ratio, any undrawn letters of credit, surety
or other bonds, or other similar instruments shall not, for the purposes of such calculation, be
included in the calculation of Debt at the end of the definition.5.
    
    The definition of EBITDA in the Second Lien Agreement shall be amended by inserting the words ;
provided, however, that, in calculating EBITDA for any Measurement Period (i) which includes the fiscal
quarter ended December 31, 2006, any Special Acquisition Expenses incurred during such fiscal quarter
shall be added to Consolidated Net Income (to the extent subtracted in calculating Consolidated Net
Income), and (ii) which includes the fiscal quarters ended March 31, 2007 or June 30, 2007, any
extraordinary, non-recurring expenses or gains incurred during such fiscal quarter shall be added to or
subtracted from, as the case may be, Consolidated Net Income (to the extent subtracted
 2




---



##### 



6.
    
    The definition of Fiscal Year in the Second Lien Agreement shall be amended by inserting the words ;
provided, further, that any Subsidiary of Endeavour International may change its Fiscal Year such that
the end of its fiscal year occurs on a date other than December 31 (including Fiscal Year 2006), so
long as (x) the Administrative Agent is given written notice of such change within 30 Business Days
after such change is effected, and (y) in no event shall any Fiscal Year be in excess of 16 months
long at the end of the definition.7.
    
    The definition of Present Value in the Second Lien Agreement shall be amended by deleting the words ,
in each case based upon the actual monthly price quoted on NYMEX for the applicable month, in effect at
the time, and inserting the words , in the case of the monthly crude oil (Dated Brent) price, based
upon the actual monthly price quoted on ICE for the applicable month, in effect at the time, and in the
case of the natural gas (NBP) price, based upon the actual monthly price quoted on Heren for the
applicable month, in effect at the time,.8.
    
    The definition of Proven Present Value in the Second Lien Agreement shall be amended by deleting the
words , in each case based upon (a) the actual monthly price quoted on NYMEX on such date for the
corresponding month through the 60th month from such date and (b) the arithmetic monthly average for
months 49 though 60 for each month after the 60th month  and inserting the words , in the case of the
monthly crude oil (Dated Brent) price, based upon (a) the actual monthly price quoted on ICE on such
date through the 60th month from such date and (b) the arithmetic monthly average for months 49 though
60 for each month after the 60th month and, in the case of the natural gas (NBP) price based upon (i)
the actual monthly price quoted on Heren on such date through the 60th month from such date and (ii)
the arithmetic monthly average for months 49 though 60 for each month after the 60th month.9.
    
    Section 8.01(a)(ii) of the Second Lien Agreement shall be amended by replacing the words and not later
than October 31st of each year in such sub-section with the words and within 12 calendar months of
the end of each applicable Fiscal Year.10.
    
    Section 8.01(a) shall be further amended by inserting the following at the end thereof: , and (iii) if
Endeavour UK or Talisman has a Fiscal Year not ending on December 31 in any calendar year, or if
Endeavour UK or Talisman has a Fiscal Year ending on December 31 but have not provided audited
financial statements, such entity shall, not later than October 31st of each year, deliver its
unaudited consolidated balance sheet and its related statement of income as of and for the previous
calendar year ended December 31, setting forth in each case, in comparative form, the figures for the
prior calendar year.11.
    
    Section 9.23 of the Second Lien Agreement shall be amended by inserting the words , provided that any
amendments to the organizational documents, by-laws and other governing documents of each Credit Party
and its Subsidiaries and to documents relating to Permitted Preferred Stock shall be permitted provided
that the rights of the Lenders under this Agreement are not adversely affected by such amendments,
modifications or changes, including but not limited to amendments, modifications or changes to provide
for new directors, stock splits, reverse stock splits, and changes to the amount of authorised common
stock at the end of that section.12.
    
    This Amendment Agreement shall take effect as of March 13, 2007, on the first date on which all of the
following conditions to effectiveness shall have occurred (the Effective Date):
 3




---



##### 



(a)
    
    All invoiced reasonable out-of-pocket expenses of the Administrative Agent (including the
reasonable fees and expenses of counsel for the Administrative Agent) in connection with the
negotiation, preparation and delivery of this Amendment Agreement and in connection with ongoing
work regarding the Second Lien Agreement shall have been paid;(b)
    
    Each of the Lenders that execute and deliver this Amendment Agreement to the Administrative
Agent prior to 12:00 pm (New York time) on March 13, 2007 shall have received from the Borrower
an amendment fee, payable in cash, in an amount equal to the principal amount of such Borrowers
respective Loans under the Facility, multiplied by 0.0010; and(c)
    
    The Administrative Agent shall have received counterparts of this Amendment Agreement executed
by the Borrower, each Guarantor and the Majority Lenders.; provided, that each of the above conditions shall occur on or before March 13, 2007.
 13.
    
    This Amendment Agreement may be executed in any number of counterparts, all of which taken together
shall constitute one and the same instrument. Any party may enter into this Amendment Agreement by
signing any such counterpart.14.
    
    Each Guarantor hereby confirms and agrees that, notwithstanding the effectiveness of this Amendment
Agreement, the Guarantee set forth in Article XII of the Second Lien Agreement is, and shall continue
to be, in full force and effect and is hereby ratified and confirmed in all respects. The Borrower and
each Guarantor hereby confirms and agrees that each Security Instrument to which it is a party, and all
of the collateral described therein does, and shall continue to, secure the payment of all of the
Obligations secured thereby.15.
    
    On and after the effectiveness of this Amendment Agreement, each reference in the Second Lien Agreement
to this Agreement, hereunder, hereof or words of like import referring to the Second Lien
Agreement, and each reference in each of the other Loan Documents to the Second Lien Credit
Agreement, thereunder, thereof or words of like import referring to the Second Lien Agreement,
shall mean and be a reference to Second Lien Agreement, as amended by this Amendment Agreement.16.
    
    The execution, delivery and effectiveness of this Amendment Agreement shall not, except as expressly
provided herein, operate as a waiver of any right, power or remedy of any Lender or the Administrative
Agent under the Second Lien Agreement or any of the other Loan Documents, nor constitute a waiver of
any other provision of the Second Lien Agreement or any of the other Loan Documents.17.
    
    The provisions of Sections 13.01 and 13.09 of the Second Lien Agreement shall apply, mutatis mutandis,
to this Amendment Agreement.
 [SIGNATURES APPEAR ON FOLLOWING PAGE]
 4




---



##### 



IN WITNESS
  Endeavour International Holding B.V.
 By
    
    /s/ Lance GillilandBy
    
    /s/ H. Don Teague




---



##### 



The other GuarantorsEndeavour International CorporationBy
    
    /s/ Lance GillilandEndeavour Operating CorporationBy
    
    /s/ Lance GillilandEND Operating Management CompanyBy
    
    /s/ Lance GillilandEND Management CompanyBy
    
    /s/ Lance GillilandEndeavour Energy Netherlands B.V.By
    
    /s/ Lance GillilandBy
    
    /s/ H. Don TeagueEndeavour Energy UK LimitedBy
    
    /s/ Lance GillilandEndeavour North Sea Limited(previously Talisman Expro Limited)By
    
    /s/ Lance Gilliland




---



##### 



The Administrative AgentCredit Suisse, Cayman Islands BranchBy
    
    /s/ Vanessa Gomez 

          Vice PresidentBy
    
    /s/ Karim Blasetti 

          Vice President