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                                                                     EXHIBIT 4.9

Unofficial English Translation of:

                               Framework Agreement

This agreement was concluded on July 1, 2002 between ESSO Deutschland GmbH
("EDG"), Deutsche Shell GmbH ("DSG") and E.ON AG ("E.ON"). EDG, DSGH and E.ON
are hereinafter each referred to individually as a "Party", and collectively as
"the Parties".

(a)      EDG and DSG are the shareholders of BEB Erdgas und Erdol GmbH ("BEB"),
         which holds shares in Ruhrgas AG ("RG").

(b)      BEB holds a stake in Schubert KG, which in turn holds shares in RG.

(c)      E.ON has informed EDG and DSG of its interest in purchasing the RG
         shares owned by BEB, and in the RG shares which are attributable to BEB
         but owned by Schubert KG (hereinafter collectively referred to as "the
         RG shares").

(d)      EDG is not prepared to accept the sale or transfer of the RG shares by
         EDG, BEB or Schubert KG to E.ON.

(e)      EDG will agree to a transfer of the RG shares to DSG by way of an
         agreement to be reached between EDG and DSG, to enable DSG to sell the
         RG shares in accordance with the above-mentioned interest in their
         purchase, subject to appropriate safeguarding of EDG's interests with
         respect to BEB.

(f)      EDG further wishes ensure that there will be no detrimental impact on
         its rights and the rights of its affiliated companies (including BEB)
         with respect to current commercial relationships and agreements with
         RG.

(g)      EDG will continue to cooperate with DSG to ensure that DSG is able to
         complete such sale of the RG shares.

(h)      EDG, DSG and E.ON have agreed to set down the necessary and appropriate
         measures required for performance of the above-mentioned transaction in
         this agreement.

NOW THEREFORE, IN CONSIDERATION OF THE ABOVE, THE PARTIES HEREBY AGREE AS
FOLLOWS:


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1.       DSG is free to sell the RG shares to E.ON according to the terms and
         conditions set down in the share purchase agreement ("Share Purchase
         Agreement") attached to the present agreement as SCHEDULE A. However,
         in order to safeguard the interests of EDG as described in the Preamble
         under letter (e) and letter (f), E.ON and DSG undertake not to make any
         significant changes to the Share Purchase Agreement or enter into any
         other significant agreements regarding the sale of the RG shares to
         E.ON or a third party designated by E.ON without prior consent in
         writing from EDG.

2.       So that the transfer of RG shares from DSG to E.ON can take place,

         (a)      EDG shall allow the transfer of the RG shares to DSG prior to
                  the transfer of the RG shares to E.ON or any other
                  shareholders exercising their first option and pre-emptive
                  rights for the RG shares, and shall cooperate to the best of
                  its ability in implementing such transfer;

         (b)      EDG shall use its best efforts to ensure that Schubert KG
                  waives the first option rights set down in the Investor Rights
                  Agreements of January 9, 1966 and March 28, 1968 between the
                  RG shareholders and RG (hereinafter referred to as the
                  "Investor Rights Agreements") and that it approves the
                  transfer of the RG shares in the General Meeting of
                  Shareholders of RG;

         (c)      the Parties shall use their best efforts to ensure that the
                  transfer of all the shares pursuant to Schedule A of the Share
                  Purchase Agreement, the Schubert Agreement referred to in
                  Section 4 par. 1 of the Share Purchase Agreement and, if
                  applicable, acquisition under first option rights are all put
                  to a vote at the same time in the General Meeting of
                  Shareholders of Ruhrgas AG;

         d)       EDG and DSG undertake, each on condition of assurance that
                  the performance of the Share Purchase Agreement by E.ON and
                  DSG will be able to proceed, to exert their influence under
                  company law, and within the possibilities legally available to
                  them, to ensure that the parties with voting rights on the
                  basis of the RG shares sold pursuant to Section 1 par. 1 of
                  the Share Purchase Agreement give their approval at general
                  meetings of shareholders of RG for all other intended sales of
                  RG shares to E.ON by other RG shareholders. The extent of the
                  obligation incumbent on EDG and DSG under the present
                  agreement shall in no circumstances exceed the extent of the
                  obligation incumbent on DSG under the Share Purchase
                  Agreement;

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         (e)      EDG and DSG undertake to guarantee in the case of BEB, and
                  each to use their best efforts in the case of Schubert KG, to
                  ensure that BEB and Schubert KG each gives its approval to a
                  transfer of the RG shares held by Heinrich Industrie AG
                  (based in Essen, Germany) to E.ON. Each company also hereby
                  waives its first option and pre-emptive rights with respect
                  to those shares;

         (f)      to the extent that EDG has undertaken under this Clause 2 to
                  "use its best efforts", this does not denote any obligation to
                  make any financial or other business concessions.

3.       (a)      If E.ON does not succeed in obtaining antitrust approval for
                  the acquisition by E.ON of a majority of all shares issued by
                  Ruhrgas AG by means of the applications referred to in Clause
                  3 letter (c), in particular the procedure currently pending
                  before the Federal Minister for the Economy and Technology
                  referred to in that paragraph, DSG and E.ON shall immediately
                  jointly state whether and by what means, under the de facto
                  and de jure conditions then prevailing, E.ON's merger project
                  for the acquisition of a majority of all shares issued by
                  Ruhrgas AG, which includes the Share Purchase Agreement and
                  the Schubert Agreement referred to in Section 4 par. 1 of the
                  Share Purchase Agreement, can be realized. That may involve
                  changes to the prerequisites for performance of the Share
                  Purchase Agreement.

         (b)      Immediately after receipt of a ministerial approval for the
                  merger project referred to in Clause 3 letter (c), E.ON shall
                  approach the Federal Cartel Office, using language according
                  to the draft letter provided as SCHEDULE B (with carbon copy
                  to the Merger Task Force of the EU Commission), requesting
                  written confirmation that following performance of the
                  indirect acquisition of a majority stake in Ruhrgas AG via the
                  acquisition of majority stakes in Bergemann GmbH and
                  Gelsenberg AG (Acquisition of Control), the acquisition of the
                  RG shares will not constitute a merger situation subject to
                  application for approval. In the event that the Federal Cartel
                  Office or the EU Commission takes the view that the
                  acquisition of RG shares envisaged in the Share Purchase
                  Agreement and the acquisition of RG shares envisaged in the
                  Schubert Agreement referred to in Section 4 par. 1 of the
                  Share Purchase Agreement will constitute another merger
                  situation subject to application for approval under antitrust
                  provisions, DSG and E.ON shall forward an application to the
                  Federal Cartel Office or the EU Commission seeking such
                  approval, and shall support the application to the best of
                  their ability. The Parties are not obliged to accept any
                  commitments given to, or requirements and conditions imposed
                  by, the Federal Cartel Office or the EU Commission, or to
                  cooperate in their practical implementation. This also applies
                  with respect to agreements not specifically referred to in
                  Clause 3 letter (e).


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                  If the Federal Cartel Office does issue a letter of caution in
                  relation to the merger project referred to in this paragraph
                  (b), immediately upon receiving the document the Parties shall
                  engage in frank and constructive discussions with a view to
                  referring the project described in the application, in the
                  event of a rejection, to the Federal Minister for the Economy
                  and Technology for approval. The interests of both Parties
                  shall be given reasonable consideration in the discussions,
                  but the decision on such referral shall ultimately be at the
                  sole discretion of E.ON.

         (c)      At the time of the signing of the Share Purchase Agreement, a
                  procedure is already pending before the Federal Cartel Office
                  and the Federal Minister for the Economy and Technology ("the
                  Minister"; the Minister and the Federal Cartel Office are
                  hereinafter collectively referred to as "the Antitrust
                  Authorities") (Gelsenberg application of August 15, 2001 and
                  petition for ministerial approval of February 18, 2002;
                  Bergemann application of November 9, 2001 and petition for
                  ministerial approval of March 5, 2002), in which E.ON is
                  seeking antitrust approval for the acquisition of majority
                  stakes in Bergemann GmbH and Gelsenberg AG (indirect
                  acquisition of a majority stake in Ruhrgas AG).

         (d)      E.ON shall immediately inform EDG in writing of the details of
                  the procedure initiated pursuant to Clause 3 letter (a) or
                  letter (b) of this agreement, especially where the interests
                  of EDG or its affiliated businesses may be involved, and EDG
                  is not aware of this information by virtue of itself being a
                  party in the procedure. The same applies to EDG.

         (e)      In the event of conditions or requirements being imposed on
                  E.ON in one of the procedures referred to in Clause 3, letters
                  (a) to (c) involving direct intervention in the natural gas
                  supply contracts between BEB - alone or with others - and
                  Ruhrgas AG, E.ON is obliged to notify EDG immediately of this
                  situation. EDG shall be entitled to withdraw from the present
                  agreement by notification in writing within 30 business days
                  of being notified by E.ON in writing of the imposition of the
                  said conditions. An intervention in this sense is deemed to
                  have occurred, for example, if changes are made in the
                  contract, if contractual rights are exercised, or if any legal
                  leeway as might exist is used. Impacts on the said contracts
                  that are merely of an indirect nature, e.g. as a result of
                  structure-related commitments (including in the context of the
                  Association Agreement) are not covered by this provision. If
                  EDG does not exercise its right of withdrawal, this shall not
                  be construed as agreement by EDG to the condition or
                  requirement so imposed, and it shall not be obliged to
                  cooperate in the practical implementation of the condition or
                  requirement following performance of the agreement.


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                  In the event of such withdrawal, E.ON and EDG undertake to
                  proceed immediately to withdraw the application regarding the
                  merger project under this agreement (including any application
                  for the granting of ministerial approval).

         (f)      In any procedure pursuant to Clause 3 letter (a) or letter
                  (b), E.ON undertakes not to propose or accept any commitments
                  to or conditions imposed by the Antitrust Authorities
                  regarding the stakes in RG without prior consultation with DEG
                  and EDG. E.ON shall further be obliged, in the event of any
                  intention on its part or by the Antitrust Authorities to
                  suggest or propose conditions or requirements in a procedure
                  pursuant to Clause 3 letter (a) or letter (b) involving a
                  direct intervention as described in Clause 3 letter (e) in the
                  commercial gas contracts referred to in that paragraph, to
                  notify EDG immediately on each occasion by way of a detailed
                  report.

         (g)      Without prejudice to the obligations incumbent on E.ON and DSG
                  under the Share Purchase Agreement, the Parties each undertake
                  to treat all information specifically marked as confidential
                  received from the other party regarding the status and content
                  of negotiations with the Antitrust Authorities in connection
                  with the antitrust procedures pursuant to Clause 3 letter (c)
                  above as "confidential information" as defined in and
                  according to the provisions of the Confidentiality Agreement
                  in place between the Parties, attached as Schedule C, with the
                  proviso that the Confidentiality Agreement shall continue to
                  apply to this extent following the signing of this agreement.

4.       (a)      EDG and DSG give a guarantee to E.ON, in the form of an
                  independent guarantee undertaking, that as of the transfer of
                  the RG shares to DSG, (i) the RG shares will be owned by BEB
                  or a 100% subsidiary company of BEB; (ii) BEB or a 100%
                  subsidiary company of BEB has been authorized to transfer the
                  RG shares to DSG; and (iii) the RG shares are not encumbered
                  with any third-party rights other than those under the
                  Bylaws of RG and the Investor Rights Agreements.

         (b)      No further guarantees are given by EDG and DSG (in the case of
                  DSG without prejudice to Section 5 of the Share Purchase
                  Agreement); without prejudice to the foregoing provisions, any
                  warranty claims by E.ON against EDG and/or DSG are precluded
                  to the extent permitted by law.

         (c)      E.ON hereby accepts that, without prejudice to Section 5 of
                  the Share Purchase Agreement, any claims invoked by E.ON
                  against DSG and/or EDG under this


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                  agreement will be combined with any claims invoked by E.ON
                  against DSG under the Share Purchase Agreement, and the joint
                  liability of EDG and DSG under this agreement, irrespective of
                  the legal reason, may not exceed the amount specified in
                  Section 5 of the Share Purchase Agreement.

         (d)      Any amounts paid to E.ON as a result of claims invoked by E.ON
                  with respect to a breach of the warranties under Clause 4
                  letter (a) above (the "Share Purchase Agreement Warranties")
                  shall be borne in equal proportions by EDG and DSG; if the
                  breach relates solely to an action or omission by EDG or DSG,
                  the party in question shall be liable for the amount
                  concerned. The same apportionment of liability between DSG and
                  EDG as described in the preceding sentence of this letter (d)
                  shall apply in the eventuality of E.ON successfully invoking
                  claims against DSG with respect to a breach of the warranties
                  pursuant to Section 5 of the Share Purchase Agreement (the
                  "Share Purchase Agreement Warranties"), if E.ON would be
                  entitled on the basis of such breach of the Share Purchase
                  Agreement Warranties to invoke claims against DSG and EDG for
                  a breach of the Share Purchase Agreement Warranties.

5.       If E.ON acquires a direct or indirect majority stake for the purposes
         of Section 15 of the German Stock Corporation Law [AktG.] in RG or
         secures control of a direct or indirect majority stake in RG, but the
         acquisition of the RG shares by E.ON under the Share Purchase Agreement
         cannot be performed, the Parties shall enter into negotiations on an
         appropriate arrangement for their future cooperation as direct or
         indirect shareholders in RG, including a discussion of the current
         first option and pre-emptive rights and the requirements for approval
         from the General Meeting of Shareholders of RG for the transfer of
         Ruhrgas shares.

6.       To the extent permitted by law, EDG shall ensure that representatives
         of BEB and its shareholders holding office in executive bodies of RG,
         and in particular the Supervisory Board, will immediately submit the
         statements required for resignation from those positions following the
         performance of the transfer of the RG shares to DSG.

7.       E.ON undertakes to EDG to use its best efforts to ensure that the
         General Meeting of Shareholders of RG does not pass any resolutions on
         an increase of the capital stock of the company prior to the
         performance of the Share Purchase Agreement or a withdrawal from the
         Share Purchase Agreement.



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8.       Without prejudice to the rights of withdrawal pursuant to Clause 3
         letter (e) of this agreement, either of the Parties may withdraw from
         this agreement:

         (a)      if the Federal Minister for the Economy and Technology has
                  denied approval for any or all of the merger projects pursuant
                  to Clause 3 letter (c) above, and (i) one or several of the
                  Parties, or all the Parties, regard continuance with the
                  merger project for the acquisition by E.ON of a majority stake
                  in Ruhrgas AG pursuant to Clause 3 letter (a) as no longer
                  offering sufficient prospects of success, or (ii) the
                  competent Antitrust Authorities (including the ED Commission)
                  have denied approval for such a merger project and the
                  deadline for submission of any appeals has expired or such
                  appeals have been unsuccessful;

         (b)      if (i) permission has been granted for all merger projects
                  pursuant to Clause 3 letter (c) and (ii) the merger projects
                  pursuant to Clause 3 letter (a) and letter (b) have been
                  prohibited by the Federal Cartel Office or the EU Commission
                  and the deadlines for applying for ministerial approval have
                  expired without any petition having been lodged, or in the
                  case of (ii) if the Federal Minister for the Economy and
                  Technology has denied a petition for ministerial approval;

         (c)      if the enforceability of an approval for merger projects
                  pursuant to Clause 3 letter (a) and - if an application has
                  been lodged - Clause 3 letter (b) has been suspended and is
                  not reinstated within two months, and in any event by
                  September 16, 2003 at the latest;

         (d)      in any event, if all the prerequisite conditions for
                  performance of the Share Purchase Agreement have not been met
                  by September 16, 2003.

         In the event of the withdrawal of one of the Parties, irrespective of
         the legal reason, any obligation on the part of the Vendor for the
         practical implementation of commitments given and/or conditions imposed
         in connection with the procedures pursuant to Clause 3 letter (a) to
         letter (c) above or their cooperation with their practical
         implementation shall cease to apply.

         Any withdrawal under this agreement must be in written form.

         The cancellation of the Share Purchase Agreement shall automatically
         lead to the termination of the present agreement.

         The Parties agree that Clause 3 letters (e) and (g), Clause 5 and
         Clauses 8 to 19 of this agreement shall continue to apply following
         termination.

9.       (a)      Immediately after the signing of this agreement and the
                  signing of the Share Purchase Agreement, whichever date is
                  later,


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                  the Parties shall issue releases for the press and the stock
                  exchanges using the language of the drafts provided here as
                  SCHEDULE D. The Parties have agreed on the catalog of
                  questions and answers attached as SCHEDULE E, which any of the
                  Parties may use at any time with reference to the provisions
                  of this agreement.

         (b)      Prior to performance of the transactions envisaged in the
                  Share Purchase Agreement, and for a period of 24 months
                  thereafter, each of the Parties may only provide answers that
                  are consistent with SCHEDULE E, and may only issue releases
                  that are consistent with SCHEDULE D, or that have been agreed
                  on in advance in writing between the Parties. The contents of
                  this agreement and all other agreements reached in connection
                  with this document, all details of the structure of the
                  transactions required and envisaged regarding the RG shares to
                  be sold pursuant to Share Purchase Agreement, and all details
                  of the individual steps in the performance of that agreement
                  shall be barred from public release, even after expiry of the
                  abovementioned period.

         (c)      The Parties shall agree on the releases to be issued on the
                  performance of this agreement.

         (d)      Unless otherwise explicitly permitted hereinabove, each of the
                  Parties agrees to keep the contents of this agreement and all
                  agreements reached in connection thereto confidential
                  vis-a-vis third parties.

         (e)      Exceptions to the above-mentioned confidentiality provisions
                  apply in the case of obligations to notify Courts or public
                  authorities on the basis of legal provisions or applicable
                  stock exchange rules.

10.      E.ON is entitled to designate a company in the E.ON group as acquiring
         party in its stead or for a portion of the RG shares to be acquired,
         provided that the company in question declares its unconditional
         willingness to join this agreement and the Share Purchase Agreement,
         and accepts the obligations pursuant to the Investor Rights Agreements,
         and provided that E.ON accepts joint and several liability for all
         obligations of the acquiring party so designated.

11.      The rights and obligations under this agreement may be transferred to
         third parties only with prior agreement in writing from the respective
         other Parties. The other Parties may however deny consent for such a
         transfer only for good cause in the case of transfer to an affiliated
         company, provided that the transferor party accepts joint and several
         liability with the transferee affiliated company, particularly where
         they would be exposed to tax risks as a result.

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12.      The following are regarded as affiliated companies:

         (a)      in the case of DSG, N.V. Koninklijke Nederlandse Petroleum
                  Maatschappij (a company organized under Netherlands law), The
                  Shell Transport and Trading Company p.l.c. (a company
                  organized under English law), and any other company
                  (irrespective of its place of registration) which at the time
                  has direct or indirect capital relationships with one or both
                  of the above companies. For the purposes of this paragraph:

                  (i)      a company has a direct capital relationship with
                           another company or companies if such company or
                           companies are beneficial owners of shares in the
                           first company, representing 50% or more of the voting
                           rights in its General Meeting of Shareholders. A
                           company has an indirect capital relationship with
                           another company or companies ("parent company" or
                           "parent companies") if there is a chain of companies
                           beginning with the parent company / parent companies
                           and ending with the company in question, so that each
                           of the companies apart from the parent company /
                           parent companies has a direct capital relationship
                           with one or more companies in the chain as defined
                           above.

                  (ii)     Affiliated companies of DSG for the purposes of this
                           agreement also include BEB and all companies with
                           capital relationships with BEB and/or DSG, if the
                           direct or indirect capital link is at least 50%, and
                           companies affiliated with them pursuant to Sections
                           15 ff. of the German Stock Corporation Law [AktG].

         (b)      in the case of EDG, ExxonMobil Corporation and any other
                  company in which ExxonMobil Corporation holds or controls,
                  directly or indirectly (i.e., via a capital link with a chain
                  of companies beginning with ExxonMobil Corporation as parent
                  company and ending with the company in question), 50% or more
                  of the shares giving voting rights, or other form of stake in
                  the equity capital associated with voting rights in the
                  General Meeting of Shareholders of the company in question.

         (c)      in the case of E.ON, each affiliated company of E.ON for the
                  purposes of Sections 15 ff. of the German Stock Corporation
                  Law [AktG]. RG shares controlled by E.ON are those shares for
                  which E.ON and/or its affiliated companies control the
                  exercise of voting rights on the basis of voting agreements or
                  similar agreements.



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13.      This agreement is subject to the law of the Federal Republic of
         Germany.

14.      Any changes or additions to this agreement, including this clause,
         shall be valid only if made in writing, unless notarial authentication
         has been stipulated.

15.      Any disputes arising in connection with this agreement or its validity
         shall be finally resolved in accordance with the Arbitration Tribunal
         Rules of the German Arbitration Institute (DIS), with exclusion of
         legal actions before the ordinary Courts. The arbitration venue is
         Frankfurt am Main. The arbitration proceedings shall be conducted in
         German.

         The inclusion of the Parties to this agreement in an arbitration
         procedure pursuant to the Share Purchase Agreement, by joining the
         procedure or by way of third party notification of dispute or providing
         assistance to one of the parties in the procedure, is permitted. The
         effect of a third party notification of dispute or provision of
         assistance shall be as set down in Section 74 par. 3 and Section 68 of
         the German Code of Civil Procedure [ZPO].

16.      If any provisions of this agreement are or become fully or partly
         legally invalid or unenforceable, this shall not affect the validity of
         the other provisions of this agreement. The same applies if a gap is
         found in this agreement. Instead of the invalid or unenforceable
         provision, or to fill the gap, a reasonable arrangement shall be deemed
         to apply which to the extent legally possible is the closest
         approximation to what the Parties intended or according to the purpose
         and general tenor of this agreement would have intended if they had
         given consideration to the point in question at the time of concluding
         this agreement or subsequently incorporating an addition provision.
         This also applies if the invalidity of a provision is based, for
         example, on a scope of performance or a time (period or deadline)
         specified in this agreement; in such cases the agreed provision shall
         be replaced with a legal scope of performance or time (period or
         deadline) which is the closest approximation to the original intention.

17.      This agreement contains all the understandings reached between the
         three Parties regarding the subject-matter of this Framework Agreement,
         and replaces any prior agreements between the Parties, whether verbal
         or in writing, explicit or tacit, on the subject-matter of this
         agreement.

18.      Failure to invoke or a delay in invoking a right or claim flowing from
         or based on this agreement or connected with this agreement does not
         denote a waiver of the said right or claim or other rights or claims.


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         Nor shall the invocation or partial invocation of a right or claim
         arising from this agreement or connected therewith impede the
         subsequent invocation of the said right or claim or other rights or
         claims.

19.      Business days for the purposes of this agreement are all banking days
         in Frankfurt am Main, Germany.

Dusseldorf, July 1, 2002

ESSO Deutschland GmbH

Deutsche Shell GmbH

E.ON AG