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                                                                    Exhibit 10.6





                             SHARE PLEDGE AGREEMENT

                                  10 APRIL 2001


                                     BETWEEN

                            PREEM HOLDINGS AB (PUBL)
                                   AS PLEDGOR

                                       AND

                              BANKERS TRUST COMPANY
                                   AS TRUSTEE


                     REGARDING SHARES IN PREEM PETROLEUM AB








                        MANNHEIMER SWARTLING ADVOKATBYRA
                                STOCKHOLM, SWEDEN

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This SHARE PLEDGE AGREEMENT is dated as of 10 April 2001 between:

PREEM HOLDINGS AB (PUBL), reg. no. 556206-9673, (the "PLEDGOR"); and

BANKERS TRUST COMPANY, as trustee on behalf of the Noteholders (as defined
below), (the "TRUSTEE").



1.    DEFINITIONS AND INTERPRETATION

1.1   DEFINITIONS

      "AGREEMENT" means this Share Pledge Agreement.

      "BUSINESS DAY" means a day (other than a Saturday or Sunday) which is not
      a public holiday and on which banks are open for general business in
      Stockholm.

      "COMPANY" means Preem Petroleum AB, reg. no. 556072-6977.

      "EVENT OF DEFAULT" has the meaning as defined in the Indenture and also
      includes any breach of this Agreement by the Pledgor.

      "INDENTURE" means the indenture dated as of 10 April 2001 by and between
      the Pledgor, Deutsche Bank AG London, as principal paying agent, and the
      Trustee governing the Notes.

      "NOTEHOLDERS" means the holders from time to time of the Notes.

      "NOTES" means the 10-5/8% senior secured notes due 2011 and any
      additional notes issued under the Indenture.

      "SECURED OBLIGATIONS" means any and all of the Pledgor's present and
      future obligations to the Trustee and the Noteholders under the Notes and
      the Indenture.

      "SECURED PARTIES" means the Trustee, on behalf of itself, and the
      Noteholders, and their successors and assignees from time to time.

      "SECURITY INTEREST" means any mortgage, pledge, lien, charge, assignment
      by way of security, hypothecation, security interest, title retention
      (other than in respect of goods purchased in the ordinary course of
      trading), sale and repurchase or sale and lease-back arrangement or any
      other agreement or arrangement in each case having the effect of
      conferring security.

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                                                                            3(2)
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      "SHARES" means (i) all the shares, being 610,258 shares (represented by
      one share certificate No. 1-610,258), in the capital of the Company,
      having a nominal value of SEK 1,000 per share and representing one hundred
      (100) per cent of the total number of shares in the Company, and (ii) such
      new shares that may be issued whether by an increase of the Company's
      share capital, or a change in the nominal value of the shares.

1.2   INTERPRETATION

1.2.1 A reference in this Agreement or in any other document referred to herein
      or delivered in connection herewith to a statute or any provision thereof
      shall refer also to that statute or provision as amended or re-enacted.

1.2.2 A reference in this Agreement or in any other document referred to herein
      or delivered in connection herewith to an agreement or document shall
      refer also to such agreement or document as amended, varied or
      supplemented and shall include all appendices and other attachments.

2.    PLEDGE AND GRANT OF SECURITY

2.1   The Pledgor hereby pledges to the Secured Parties, all of the Pledgor's
      title to and interest in the Shares as security for the due and punctual
      performance of the Secured Obligations.

2.2   Subject to the other provisions of this Agreement, the pledge includes all
      rights which derive from the Shares including, but not limited to, the
      right to participate in new or bonus issues of shares, the right to
      participate in issues of convertible debt instruments and other securities
      and the right to receive dividends whether in cash or in kind.

2.3   The Security Interest created herein shall not be affected in any way by
      any variation, extension, waiver, compromise or release of any or all of
      the Secured Obligations, the Indenture or of any security from time to
      time therefor, or by any change in the laws, rules or regulations of any
      jurisdiction or by any present or future action of any governmental
      authority or court amending, varying, reducing or otherwise affecting, or
      purporting to amend, vary, reduce or otherwise affect, any of the Secured
      Obligations or the Indenture.

2.4   This pledge shall be in addition to and independent of any other pledge,
      guarantee, or other security given in respect of the Secured Obligations.

2.5   The Secured Parties are entitled to decide in their own discretion which
      security interests and in what order such security interests shall be
      applied towards satisfaction of the Secured Obligations and the Pledgor
      shall not be entitled to claim any right to any other security given to
      the Secured Parties.

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                                                                            4(3)
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3.    PERFECTION OF SECURITY

3.1   The Pledgor shall on the date hereof deliver to the Trustee the share
      certificate evidencing the Shares endorsed in blank. Should any shares in
      the Company be issued in the future, the Pledgor shall promptly deliver to
      the Trustee any share certificates evidencing such shares endorsed in
      blank together with any coupons and other documents pertaining thereto.
      The Trustee shall hold the share certificates in Sweden on behalf of
      itself and the Noteholders.

3.2   For as long as no Event of Default has occurred, all dividends declared on
      or in respect of the Shares and any other payments with respect to the
      Shares shall be paid to the Pledgor. Following the occurrence of an Event
      of Default, and for as long as it is continuing, all dividends and any
      other payments with respect to the Shares shall be paid to the Trustee on
      behalf of the Secured Parties. Any dividends or other payments with
      respect to the Shares paid to the Trustee shall become part of the
      security created herein and be applied towards satisfaction of the Secured
      Obligations in accordance with Clause 7 of this Agreement.

3.3   The Pledgor shall on the date hereof inform the Company of the pledge and
      Security Interest over the Shares created hereby in the form attached
      hereto as SCHEDULE 1 and the Company shall have acknowledged receipt of
      such notice.

3.4   The Pledgor shall on the date hereof issue to the Trustee on behalf of the
      Noteholders a separate power of attorney in the form of SCHEDULE 2 giving
      the Trustee on behalf of the Noteholders the right to participate and vote
      for the Shares at shareholders' meetings in the Company, provided an Event
      of Default has occurred and is continuing. The Pledgor shall renew the
      power of attorney annually or from time to time, at the request of the
      Trustee, so that it remains continually in effect.

3.5   During the term of this Agreement, and except as provided below, the
      Pledgor shall have the right to vote for the Shares in a manner not
      inconsistent with the terms of this Agreement and the Indenture. Upon the
      occurrence and during the continuance of an Event of Default, the Trustee
      on behalf of the Noteholders may, at its own option and to the exclusion
      of the Pledgor, exercise all voting powers under the power of attorney
      given pursuant to Clause 3.4 hereof, as the Noteholders may direct in
      accordance with the terms of the Indenture.

3.6   The Trustee shall, when all Secured Obligations have been duly and
      irrevocably fulfilled and discharged, promptly release the Security
      Interest created hereby and return the share certificates evidencing the
      Shares and any outstanding power of attorney to the Pledgor. The Trustee
      shall promptly notify the Company that the Security Interest over the
      Shares has been so released. In

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                                                                            5(4)
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      addition, the Trustee shall promptly release the Security Interest created
      hereby to the extent requested by the Company in connection with any
      release of Collateral (as such term is defined in the Indenture) meeting
      the requirements of Section 10.3 and 10.4 of the Indenture.

4.    POWERS OF THE TRUSTEE

      For the purpose of enforcing the security created by this Agreement upo+n
      the occurrence of an Event of Default, the Pledgor irrevocably authorises
      and empowers the Trustee, on behalf of the Noteholders, or any nominee or
      agent designated by the Trustee, without notice to or assent by the
      Pledgor, to act in its own name or in the name of the Pledgor, and to do
      all acts and take any steps it deems necessary or appropriate in respect
      of the Shares or otherwise. The power of attorney set out in this Clause 4
      is irrevocable and shall be valid for as long as this Agreement remains in
      force.

5.    EXERCISE OF SHAREHOLDER RIGHTS

5.1   The Pledgor shall not vote for any resolution authorising an issue of new
      shares, convertible debt instruments or other securities in the Company
      unless the Pledgor extends the pledge contained in this Agreement to such
      issue and perfects such security in accordance with all applicable legal
      requirements.

5.2   The Pledgor shall not vote for any resolution for the reduction of the
      Company's share capital (Sw: NEDSATTNING AV AKTIEKAPITAL).

5.3   The Pledgor shall not, without the prior written consent of the Trustee,
      vote for any resolution for the winding-up (Sw: LIKVIDATION) of the
      Company, unless the winding-up is required by mandatory legislation, or
      for any resolution for the commencement of insolvency proceedings (Sw:
      konkurs), company re-organisation (Sw: FORETAGSREKONSTRUKTION) or other
      similar proceedings with respect to the Company.

6.    COVENANTS OF THE PLEDGOR

6.1   The Pledgor shall not dispose or attempt to dispose of the Shares or any
      interest therein, except in accordance with the Indenture.

6.2   The Pledgor shall not create or agree or attempt to create any Security
      Interest or third party right on or over the Shares or any interest
      therein other than the Security Interest created through this Agreement.

6.3   The Pledgor shall refrain from any acts, including assertion of any rights
      under the Articles of Association of the Company, or omissions, the
      purpose or effect



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                                                                            6(5)
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      of which is or would be that the Shares cease to exist or are encumbered
      in any way other than as a consequence of or in accordance with this
      Agreement.

6.4   The Pledgor shall at its own expense, from time to time, including upon
      reasonable request of the Trustee, do all such acts and execute all such
      documents as are necessary for giving full effect to this Agreement and
      securing to the Secured Parties the full benefit of the rights, powers and
      remedies conferred upon the Secured Parties in this Agreement.

7.    EXERCISE OF REMEDIES AND APPLICATION OF PROCEEDS

7.1   Upon notice being served on the Trustee under Clause 7.5 of the Indenture
      following the occurrence of an Event of Default and at all times
      thereafter, so long as the same shall be continuing, the Trustee: (i)
      shall concurrently serve such notice on the Pledgor, and (ii) may, in its
      sole discretion and in addition to any other remedies provided herein or
      by applicable law, sell the Shares or any part thereof publicly or
      privately, for cash or other consideration, after the Trustee has given
      the Pledgor ten (10) Business Days' prior written notice of the time and
      place of any such public sale, or the time after which any such private
      sale may be made.

7.2   If the Trustee, any of the Secured Parties or any party affiliated with
      the Trustee or any of the Secured Parties, purchases the Shares or any
      part thereof at a private sale following an application of Clause 7.1
      hereof, an independent valuation agency, appointed by the Stockholm
      Chamber of Commerce, shall be engaged as an expert to determine the fair
      market value of the Shares or the part thereof. The Trustee shall procure
      that any purchaser under this Clause 7.2 hereof shall pay (in cash or
      other consideration) to the Trustee the difference, if any, between such
      determined value and the price initially paid by such purchaser for the
      Shares or the part thereof.

7.3   The Trustee shall not be liable for any loss arising from or in connection
      with the enforcement of its rights under this Agreement or the sale or
      disposal of the Shares or any part thereof provided that the Trustee has
      acted in accordance with the standards set forth in the Indenture.

7.4   All reasonable costs and expenses (including legal fees) incurred by the
      Trustee or the Secured Parties in connection with the enforcement of the
      security created by this Agreement shall be borne by the Pledgor and the
      Pledgor shall indemnify and hold the Trustee and the Secured Parties
      harmless in respect of such costs and expenses. All costs and expenses
      shall be included in the Secured Obligations. This indemnity shall survive
      the termination of this Agreement, and the resignation and removal of the
      Trustee.


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                                                                            7(6)
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7.5   Chapter 10 of the Swedish Commercial Code (Sw: HANDELSBALKEN) shall not
      apply to the exercise of the powers of sale as stated in Clause 7.1
      hereof.

7.6   All moneys (or other consideration) received by the Trustee, or its
      designee, in exercise of the rights, powers and remedies under this
      Agreement or by law shall be applied by the Trustee in discharge of the
      Secured Obligations in the manner and order determined by the Trustee, in
      accordance with the terms of the Indenture. When all Secured Obligations
      have been fully and irrevocably discharged, the surplus (if any) shall be
      paid to the Pledgor.

8.    REPRESENTATIONS AND WARRANTIES

8.1   The Pledgor represents and warrants that:

      (a)   it is a limited liability company, duly incorporated and validly
            existing under the laws of Sweden, with full power and authority to
            carry on its business as it is being conducted and to execute and
            perform all of its obligations under this Agreement and all action
            required to authorise such execution and performance has been duly
            taken;

      (b)   the execution and performance of this Agreement will not violate any
            applicable law or regulation or contravene any provision of its
            Articles of Association or any agreement or arrangement to which the
            Company or the Pledgor is a party; and

      (c)   this Agreement constitutes a legally valid and perfected pledge over
            the Shares, implying obligations of the Pledgor, enforceable in
            accordance with its terms.

8.2   The Pledgor further represents and warrants that:

      (a)   the Pledgor has full ownership of the Shares and no Security
            Interest is in existence over the Shares or any part thereof or
            interest therein, except the Security Interest created hereby;

      (b)   the Company is duly incorporated and validly existing under the laws
            of Sweden as a limited liability company;

      (c)   the Shares have been duly authorised, validly issued and fully paid
            and constitute one hundred (100) per cent of the Company's issued
            share capital and no coupons or other documents pertaining to the
            Shares exist;

      (d)   neither the Pledgor nor the Company has issued, granted or entered
            into any outstanding options, warrants or other rights of any kind,
            the


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                                                                            8(7)
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            content of which includes a right to acquire, or an obligation to
            issue, shares or other equity interests in the Company; and

      (e)   the Company has not taken any action nor have any steps been taken
            or legal proceedings been started or threatened against it for its
            winding-up (Sw: LIKVIDATION) or re-organisation (Sw:
            FORETAGSREKONSTRUKTION) or for the commencement of insolvency
            proceedings (Sw: KONKURS), appointment of a liquidator,
            administrator or similar officer of it or of any part of its assets.

9.    MISCELLANEOUS

9.1   The Trustee and any Secured Party may assign its rights and obligations
      hereunder without the consent of the Pledgor, in accordance with the
      Indenture. The Pledgor shall take all reasonable action necessary to
      preserve the Security Interest created hereunder in connection with any
      such assignment.

9.2   No delay or omission in exercising any powers or privileges hereunder
      shall be construed as a waiver thereof. Any exercise of any part of the
      rights shall not preclude subsequent enforcement of any such rights which
      have not, or have not fully, been exercised.

9.3   No amendment to this Agreement shall be effective against any party unless
      made in writing and signed by such party hereto.

10.   LIMITATION OF THE TRUSTEE'S AND THE SECURED PARTIES' LIABILITY

10.1  Neither the Trustee nor any of the Secured Parties shall be held
      responsible for any damage arising out of any Swedish or foreign legal
      enactment, or any measure taken by a Swedish or foreign public authority,
      or war, strike, lockout, boycott, blockade or any other similar
      circumstance. The reservation in respect of strikes, lockouts, boycotts
      and blockades applies even if the Trustee or any Secured Party itself
      takes such measures, or is subject to such measures.

10.2  Neither the Trustee nor any of the Secured Parties shall incur any
      liability to the Pledgor pursuant to this Agreement provided that the
      Trustee has acted in accordance with the standards set forth in the
      Indenture. The Trustee and the Secured Parties shall not in any case be
      held responsible for any indirect or consequential damage.

10.3  Should an obstacle described in Clause 10.1 hereof arise which prevents
      the Trustee and/or the Secured Parties from taking any action required to
      comply with this Agreement, such action may be postponed until the
      obstacle has been removed.

10.4  The rights and duties of the Trustee are subject to the terms of the
      Indenture and in case of any discrepancy between the terms of this
      Agreement and the Indenture, the Indenture shall prevail.


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                                                                            9(8)
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11.   NOTICES

11.1  All notices or other communications under or in connection with this
      Agreement shall be in the English language and be given by letter or by
      telefax (and, in the case of telefax, confirmed by letter). Any such
      notice will be deemed to be given as follows:

      (a)   if by letter, when delivered to the address notified in accordance
            with Clause 11.3 hereof; and

      (b)   if by telefax, when received.

11.2  Any notice received on a non-working day or after business hours in the
      place of receipt will only be deemed to be given on the next working day
      in that place.

11.3  The address and telefax number of each party for all notices under or in
      connection with this Agreement are:

      The Pledgor:             Preem Holdings AB (publ)
                               Attention: Richard Ohman
                               Biblioteksgatan 29
                               P.O. Box 5785
                               SE-114 87 Stockholm
                               Sweden
                               Telephone: +46 8 614 13 00
                               Telefax: +46 8 614 13 14

       The Trustee:            Bankers Trust Company
                               Four Albany Street
                               Corporate Trust and Agency Services
                               New York, NY 10006
                               USA
                               Attention: Carol Ng
                               Telephone: +1 212 250 61 47
                               Telefax: +1 212 250 09 33

      or any other address notified by one party to the other parties by not
      less than five (5) Business Days' notice.

12.   GOVERNING LAW AND JURISDICTION

12.1  This Agreement shall be governed by and construed in accordance with
      Swedish law.

12.2  The Pledgor submits to the non-exclusive jurisdiction of the courts of
      Sweden in relation to any matter arising out of or in connection with this
      Agreement. The City Court of Stockholm shall be court of first instance.
      Nothing herein shall require the Trustee to consent to venue or submit to
      the jurisdiction of non-US courts.

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                                                                           10(9)
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IN WITNESS WHEREOF, this Agreement has been signed in two (2) originals, of
which the parties have received one each.


BANKERS TRUST COMPANY


/s/ Aileen McCormack               /s/ C.A. Morris
-------------------------          ------------------------
Name: Aileen McCormack             Name: C.A. Morris


PREEM HOLDINGS AB (publ)


/s/ Karim Karaman                  /s/ Richard Ohman
-------------------------          ------------------------
Name: Karim Karaman                Name: Richard Ohman





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                                                                            1(1)
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                                                                      SCHEDULE 1



To:  Preem Petroleum AB
     Attention: [TITLE]



NOTIFICATION OF PLEDGE OF SHARES

This is to notify you that pursuant to a pledge agreement dated 10 April 2001
(the "PLEDGE AGREEMENT") between Preem Holdings AB (publ) (the "PLEDGOR") and
Bankers Trust Company, as Trustee, on behalf of itself and on behalf of the
Noteholders (the "TRUSTEE"), the Pledgor has pledged 610,258 shares, in the
capital of Preem Petroleum AB (the "COMPANY") and such new shares as may be
issued following an increase or other change of the Company's share capital (the
"SHARES") to the Secured Parties, which are represented by the Trustee, as
security for the Secured Obligations. Capitalised terms not defined herein shall
have the meanings ascribed to them in the Pledge Agreement.

The pledge includes all rights derived from the Shares, including, but not
limited to, the right to participate in new or bonus issues of shares, the right
to participate in issues of convertible debt instruments and other securities,
and the right to receive dividends whether in cash or in kind. Any dividend
shall be paid to the Pledgor until other instructions are given by the Trustee,
subject to the terms of the Pledge Agreement.

The Pledgor has by way of power of attorney empowered any person duly appointed
by the Trustee to attend all general meetings of the shareholders of the Company
as the Pledgor's representative and to vote at such general meeting for all
shares owned by the Pledgor, provided an Event of Default under the Indenture or
the Pledge Agreement has occurred and is continuing. The power of attorney is
irrevocable and will, when the Trustee certifies to you that an Event of Default
under the Indenture or the Pledge Agreement has occurred and is continuing,
exclude the Pledgor from exercising the voting rights at the general meeting of
shareholders in the Company.

Please acknowledge receipt of this letter by signing in the space provided below
and returning a copy of this letter to each of the Pledgor and the Trustee.



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                                                                            2(2)
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Date: [DATE]

PREEM HOLDINGS AB (publ)


----------------------------                      --------------------------
Name:                                             Name:

                             ----------------------


We hereby acknowledge receipt of the above notification of pledge of shares and
confirm that the pledge has been noted in the share register. We further confirm
that we have not prior to the date hereof been notified of any pledge over the
Shares.


Date: [DATE]

PREEM PETROLEUM AB


----------------------------                      --------------------------
Name:                                             Name:


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                                                                            1(1)
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                                                                      SCHEDULE 2



                                POWER OF ATTORNEY



This power of attorney is issued pursuant to a pledge agreement dated 10 April
2001 (the "PLEDGE AGREEMENT") between Preem Holdings AB (publ) (the "PLEDGOR")
and Bankers Trust Company (the "TRUSTEE") on behalf of certain Noteholders (as
defined in the Pledge Agreement).

The Pledgor hereby empowers any person duly appointed by the Trustee to attend
all general meetings of the shareholders in Preem Petroleum AB, reg. no.
556072-6977, (the "COMPANY") and to vote at such general meetings for all shares
in the Company owned by the Pledgor, provided that the Trustee certifies to the
Company that an Event of Default under the Indenture or the Pledge Agreement has
occurred and is continuing.

This power of attorney is irrevocable and will, when the Trustee certifies that
a Event of Default under the Pledge Agreement has occurred and is continuing,
exclude the Pledgor from exercising the voting rights at the general meeting of
shareholders of the Company. This power of attorney may not be used prior to the
time of such certification.

This power of attorney shall in all respects be governed by and construed in
accordance with the laws of Sweden.

This power of attorney becomes effective on the date it is signed by the Pledgor
and it shall remain in force for one year from such date.


Date: [DATE]

PREEM HOLDINGS AB (publ)


-----------------------                      ---------------------
Name:                                        Name: