<PAGE>

                                                                    EXHIBIT 4.58

C L I F F O R D                                                   CONFORMED COPY

C H A N C E

P U N D E R

                           MARCONI COMMUNICATIONS GMBH

                                   AS ASSIGNOR

                                       AND

                   THE LAW DEBENTURE TRUST CORPORATION P.L.C.

                               AS SECURITY TRUSTEE

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

                           GLOBAL ASSIGNMENT AGREEMENT

                                (GLOBALABTRETUNG)

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

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                                    CONTENTS

<TABLE>
<CAPTION>
                                 CLAUSE                                                                   PAGE
<S>                                                                                                       <C>
1.       Definitions and languages....................................................................      3

2.       Secured Obligations..........................................................................      4

3.       Assignment...................................................................................      4

4.       Transfer of Ancillary Rights.................................................................      5

5.       List of Receivables..........................................................................      5

6.       Further Assurance............................................................................      6

7.       Retention of Title...........................................................................      6

8.       Blank Notification Letters...................................................................      7

9.       Sale of Collateral...........................................................................      7

10.      Collection of Receivables and Insurance Proceeds by the Assignor.............................      8

11.      Right to Realisation upon Enforcement Event..................................................      8

12.      Limitation of Security.......................................................................      9

13.      Release (Sicherheitenfreigabe)...............................................................     10

14.      Right of Inspection..........................................................................     11

15.      Bookkeeping and Data-Processing..............................................................     11

16.      Undertakings.................................................................................     12

17.      Expenses, Costs and Taxes....................................................................     13

18.      Partial Invalidity; Waiver...................................................................     14

19.      Amendment; Waiver............................................................................     14

20.      Notices and their Language...................................................................     14

21.      Applicable Law; Jurisdiction.................................................................     16

23.      Effectiveness................................................................................     16

24.      Counterparts.................................................................................     17
</TABLE>

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<TABLE>
<S>                                                                                                       <C>
Schedule 1 List of Receivables........................................................................     18

Schedule 2 List of Insurances.........................................................................     19

Schedule 3 Form of Notification.......................................................................     20

Schedule 4 Form of Notification.......................................................................     23

Schedule 5 List of Accounts...........................................................................     25
</TABLE>

<PAGE>

THIS GLOBAL ASSIGNMENT AGREEMENT is made the 16th day of May 2003

BETWEEN:

1.       Marconi Communications GmbH, a limited liability company organised
         under the laws of the Federal Republic of Germany, having its business
         address at GerberstraBe 33, D-71522 Backnang, which is registered
         in the commercial register (Handelsregister) of the local court
         (Amtsgericht) of Backnang under HRB 1563 (the "ASSIGNOR"); and

2.       The Law Debenture Trust Corporation p.l.c., having its business address
         at Fifth Floor, 100 Wood Street, London, EC2V 7EX, England in its
         capacity as security trustee under the Relevant Documents (the
         "SECURITY TRUSTEE").

WHEREAS:

(A)      Marconi Corporation p.l.c. (the "ISSUER") has agreed to issue the
         following notes:

         (i)      USD equivalent of GBP 450,000,000 senior secured notes due
                  2008;

         (ii)     USD 300,000,000 plus USD equivalent of GBP 117,270,000 of
                  junior secured notes due 2008;

                  the notes under (i) being documented in a senior note
                  indenture dated on or about 19 May 2003 between, inter alios,
                  the Issuer and Law Debenture Trust Company of New York as
                  Senior Note Trustee and the notes under (ii) being documented
                  in a junior note indenture dated on or about 19 May 2003
                  between, inter alios, the Issuer and JPMorgan Chase Bank as
                  Junior Note Trustee (together the "INDENTURES").

(B)      The security created by or pursuant to this Agreement is to be granted
         to and administered by the Security Trustee for itself and as trustee
         of the Secured Creditors pursuant to the relevant provisions of a
         security trust and intercreditor deed dated on or about 19 May 2003
         between, inter alios, the Issuer, Law Debenture Trust Company of New
         York as Senior Note Trustee, JPMorgan Chase Bank as Junior Note
         Trustee, the Security Trustee and the Obligors (as defined therein
         including the Assignor) as amended from time to time (the "SECURITY
         TRUST AND INTERCREDITOR DEED").

(C)      The Assignor has agreed to assign the Receivables (as defined below) as
         security for the payment and discharge of the Secured Obligations (as
         defined below) subject to the terms and conditions set out herein.

                                      - 2 -

<PAGE>

NOW, IT IS AGREED as follows:

1.       DEFINITIONS AND LANGUAGES

1.1      In this Agreement:

         "AUTHORIZATION" has the meaning given to it in Clause 10.

         "CONTINUING" in relation to an Enforcement Event, shall be construed as
         a reference to an acceleration of any Secured Obligation (other than
         Secured Obligations arising under the New Bonding Facility Agreement)
         where such acceleration has not been rescinded in writing or a
         declaration that the Secured Obligations (other than Secured
         Obligations arising under the New Bonding Facility Agreement) are
         prematurely due and payable (other than solely as a result of it
         becoming unlawful for a Secured Creditor to perform its obligations
         under the Relevant Documents) where such declaration has not been
         revoked in writing or any failure by an Obligor to pay any principal
         amount in respect of any Secured Obligations (other than Secured
         Obligations arising under the New Bonding Facility Agreement) whether
         on maturity or otherwise which has not been waived in writing. For the
         purposes of this definition of "continuing" the expression "Secured
         Obligations" shall have the same meaning as in the Security Trust and
         Intercreditor Deed.

         "RECEIVABLES"

         (a)      all present and future rights and claims owing to the Assignor
                  and originating from selling goods and/or providing services
                  (Lieferungen und Leistungen) (including, without limitation,
                  those specified in Schedule 1 hereto); and

         (b)      all present and future rights and claims to which the Assignor
                  now is or hereafter may become entitled to in respect of all
                  present and future insurance contracts or any part thereof
                  other than insurances for the benefit of third parties
                  (including, without limitation, those specified in Schedule 2
                  hereto) (collectively the "INSURANCE CONTRACTS").

         "SECURED OBLIGATIONS" has the meaning given to it under clause 2.

         "SECURITY TRUST AND INTERCREDITOR DEED" has the meaning given to it in
         Clause (B) of the recitals.

                                      - 3 -

<PAGE>

1.2      Unless otherwise defined herein or unless the context requires,
         capitalised terms shall have the same meaning as ascribed thereto in
         the Security Trust and Intercreditor Deed.

1.3      This Agreement is made in the English language. For the avoidance of
         doubt, the English language version of this Agreement shall prevail
         over any translation of this Agreement. However, where a German
         translation of a word or phrase appears in the text of this Agreement,
         the German translation of such word or phrase shall prevail.

1.4      The parties hereto each acknowledge that the Security Trustee, when
         acting hereunder, shall, to the extent permitted under the laws of
         Germany, be acting in accordance with and subject to the terms of the
         Security Trust and Intercreditor Deed.

2.       SECURED OBLIGATIONS

         The assignment hereunder (the "ASSIGNMENT") is constituted in order to
         secure together with other security granted by the Assignor the prompt
         and complete satisfaction of any and all obligations (present and
         future, actual and contingent) which are (or are expressed to be) or
         become owing by the Assignor to the Secured Creditors or any of them
         (including any future assignee or transferee of any of the Secured
         Creditors by way of transfer or assignment (including by way of
         assumption of debt (Vertragsubernahme)) under the Relevant Documents
         (including, but not limited to the parallel obligations of the Assignor
         pursuant to clause 3 of the Security Trust and Intercreditor Deed to
         pay to the Security Trustee sums equal to the sums owed by the Assignor
         to the Secured Creditors or any of them) (the "SECURED OBLIGATIONS") up
         to an aggregate amount of EUR 170 million.

3.       ASSIGNMENT

3.1      The Assignor hereby assigns the Receivables to the Security Trustee in
         its capacity as Security Trustee for the benefit of the Secured
         Creditors.

         In the event that the Assignor maintains a current account arrangement
         (Kontokorrentverhaltnis) with its customers, this Assignment includes
         all claims from any existing or future current account balances, the
         right to determine the net balance and the right to terminate the
         current account relationship.

3.2      The Security Trustee hereby accepts the assignment of the Receivables.

                                      - 4 -

<PAGE>

3.3      The existing Receivables shall pass over to the Security Trustee on
         execution of this Agreement, and any future Receivables shall pass over
         to the Security Trustee at the date such Receivables arise.

3.4      The parties to this Agreement acknowledge that the assignment of the
         Receivables may be subject to consent by third party debtors.

4.       TRANSFER OF ANCILLARY RIGHTS

4.1      Together with all the Receivables assigned and transferred in
         accordance with this Agreement, all securities, collateral and all
         ancillary rights pertaining thereto including transport insurance
         claims, as well as all rights resulting from the underlying agreements
         (hereinafter together with the Receivables referred to as the
         "COLLATERAL"), are hereby transferred and/or assigned to the Security
         Trustee, who accepts this transfer and/or assignment, to the extent
         such rights are not automatically transferred to the Security Trustee
         pursuant to Section 401 of the German Civil Code (Burgerliches
         Gesetzbuch). The Assignor's claims to demand repossession against the
         direct possessor are assigned to the Security Trustee, who accepts this
         assignment, at the same time.

4.2      If and to the extent the Assignor is in direct possession of the
         Collateral, the delivery of such Collateral shall be substituted by the
         Assignor holding the Collateral in gratuitous custody for the Security
         Trustee.

5.       LIST OF RECEIVABLES

5.1      Upon the occurrence of an Insolvency Event of Default or upon request
         of the Security Trustee if the Security Trustee has been so instructed
         pursuant to the Security Trust and Intercreditor Deed upon or at any
         time after the occurrence of an Event of Default which is continuing
         the Assignor shall, within ten (10) Business Days of the occurrence of
         the Insolvency Event of Default or request following an Event of
         Default (as the case may be), deliver to the Security Trustee a list on
         a computer disk or in such other form as agreed between the Security
         Trustee and the Assignor, containing information on the Receivables.

5.2      In the event the Security Trustee, having used its reasonable efforts,
         has been unable to access any computer disk, the Assignor undertakes to
         provide the Security Trustee, upon request by the Security Trustee,
         with a computer print-out of the Receivables in addition to, or instead
         of, the computer disks referred to under Clause 5.1.

                                      - 5 -

<PAGE>

5.3      The list referred to in Clause 5.1 is for notification purposes only
         and if for any reason whatsoever the relevant Receivables are not, or
         are incompletely contained in the list presented, then the assignment
         of the Collateral shall not be affected thereby.

5.4      Unless otherwise agreed, the list under Clause 5.1 shall show the names
         and addresses of the third-party debtors (each a "DEBTOR" and together
         the "DEBTORS") or the insurers (each an "INSURER" and together the
         "INSURERS"), as the case my be, as well as the outstanding amounts and
         the due dates for payment.

5.5      Upon the occurrence of an Insolvency Event of Default or upon request
         of the Security Trustee if the Security Trustee has been so instructed
         pursuant to the Security Trust and Intercreditor Deed upon or at any
         time after the occurrence of an Event of Default and if the Assignor
         employs a third party for its bookkeeping and/or data-processing then
         the Assignor hereby authorises the Security Trustee to obtain the lists
         directly from such third party at the Assignor's expense.

6.       FURTHER ASSURANCE

         Insofar as additional documents, declarations or actions (including
         making all filings and registrations) are necessary for the creation,
         perfection, protection or maintenance of the security interests created
         (or purported to be created) hereunder (or any of them) in favour of
         the Security Trustee or for the exercise of all rights, powers and
         remedies of the Security Trustee provided by or pursuant to this
         Agreement or by law or to facilitate (including making all filings and
         registrations) the realisation of the security interests created (or
         purported to be created) hereunder (or any of them), the Assignor shall
         at the Security Trustee's request enter into or provide such documents,
         make such declarations and/or undertake such actions at the Assignor's
         cost and expense.

7.       RETENTION OF TITLE

7.1      If Receivables are assigned pursuant hereto which are subject to
         extended retention of title arrangements (verlangerter
         Eigentumsvorbehalt), the assignment shall only become effective upon
         the termination of the extended retention of title. As long as any
         person is only partly entitled to the Receivables as a result of such
         person's retention of title arrangement, the assignment of such
         receivables to the Security Trustee hereunder shall be limited to the
         part of the Receivables to which the Assignor is entitled, the
         assignment of the other part shall be effective upon complete
         termination of the extended retention of title.

                                      - 6 -

<PAGE>

7.2      If the Assignor is entitled to a reassignment of a claim assigned to a
         supplier pursuant to an extended retention of title arrangement or to
         the proceeds paid to the supplier by third party debtors, the Assignor
         assigns to the Security Trustee the aforementioned claims and rights
         with all ancillary rights pertaining thereto. The same applies to any
         possible inchoate right (Anwartschaftsrecht) with respect to the
         Assignment of any Receivables which is subject to a dissolving
         condition. The Security Trustee is authorised but not obligated to
         discharge the extended retention of title by paying the relevant funds
         to the supplier.

8.       BLANK NOTIFICATION LETTERS

         The Assignor hereby authorises the Security Trustee to notify the
         Debtors and the Insurers on behalf of the Assignor of the Assignment
         pursuant to this Agreement. The Security Trustee shall only make use of
         such authorization upon (i) the occurrence of an Insolvency Event of
         Default or (ii) if the Security Trustee has been so instructed pursuant
         to the Security Trust and Intercreditor Deed upon or at any time after
         the occurrence of an Event of Default which is continuing.

         Upon request by the Security Trustee either (i) after an Insolvency
         Event of Default or (ii) if the Security Trustee has been so instructed
         pursuant to the Security Trust and Intercreditor Deed upon request by
         the Security Trustee upon or at any time after the occurrence of an
         Event of Default which is continuing, the Assignor shall deliver to the
         Security Trustee notification letters in the form of Schedule 3 and
         Schedule 4 (and, if so required by the Security Trustee, translated
         into the German language) executed in blank for the purpose of
         notifying the Debtors and Insurers of this Agreement. The Assignor
         hereby authorises the Security Trustee to copy such blank notification
         certificates signed by the Assignor.

9.       SALE OF COLLATERAL

         So long as the Security Trustee has not revoked the right of the
         Assignor to collect the Receivables pursuant to Clause 10, the
         Transferor may dispose of or otherwise deal with the Collateral except
         as expressly prohibited under the terms of the Indentures.

         The sale of Receivables by the Assignor through genuine factoring
         transactions shall be restricted as provided in the Relevant Documents.

                                      - 7 -

<PAGE>

10.      COLLECTION OF RECEIVABLES AND INSURANCE PROCEEDS BY THE ASSIGNOR

         The Security Trustee authorises the Assignor to collect the Receivables
         provided that payments on the Receivables are made into the accounts
         specified in Schedule 5 or if made elsewhere are transferred by the
         Assignor into these accounts (such authorization hereinafter referred
         to as the "AUTHORIZATION"). The Security Trustee may revoke the
         Authorization at any time after the occurrence of an Insolvency Event
         of Default and the Security Trustee shall revoke the Authorisation if
         the Security Trustee has been so instructed pursuant to the Security
         Trust and Intercreditor Deed upon or at any time after the occurrence
         of an Event of Default which is continuing, whereupon the Assignor may
         continue to collect the Receivables but shall promptly surrender the
         proceeds to the Security Trustee. Until the requirements set out in
         Clause 11.1 are met the Security Trustee shall treat such proceeds as
         additional collateral for the Secured Obligations. To the extent that
         the Authorization is revoked, the Security Trustee may request that
         copies of all documents relating to the Receivables be handed over to
         it and the Assignor hereby agrees to comply with any such request. For
         the avoidance of doubt nothing in this Clause 10 shall restrict the
         right of the Security Trustee to enforce its rights under Clause 11 if
         the requirements set out in Clause 11.1 are met.

11.      RIGHT TO REALISATION UPON ENFORCEMENT EVENT

11.1     At any time after the occurrence of an Enforcement Event which is
         continuing and the Security Trustee (acting on instructions received
         pursuant to the terms of the Security Trust and Intercreditor Deed)
         giving notice to the Issuer thereof and if any of the Secured
         Obligations became due and payable the Security Trustee shall, in its
         discretion, be entitled to notify the Debtors of this Agreement and
         arrange for the collection or disposal of the Receivables for and on
         behalf of the Secured Creditors in accordance with the provisions of
         this Clause 11.

11.2     The Security Trustee will notify the Assignor in writing at least five
         (5) Business Days prior to the disclosure of any assignment pursuant
         hereto. No such notice shall be required if (i) the Assignor has
         generally ceased to make payments, (ii) an application for the
         institution of insolvency proceedings is filed by or against the
         Assignor or (iii) there is reason to believe that observance of the
         notice period will affect the security interest of the Security Trustee
         in a material adverse way.

11.3     To the extent that the Authorization is revoked, the Security Trustee
         may request that originals of all documents relating to the Receivables
         be handed over to it and the Assignor hereby agrees to comply with any
         such request.

                                      - 8 -

<PAGE>

11.4     The Security Trustee shall realise all or part of the Collateral to the
         extent necessary to satisfy any outstanding Secured Obligations by
         collecting all or part of the Receivables, it being understood that the
         Security Trustee shall apply the proceeds of such realisation towards
         the Secured Obligations in accordance with and subject to the terms of
         the Security Trust and Intercreditor Deed.

11.5     The Security Trustee may request the Assignor to collect the
         Receivables for and on behalf of the Secured Creditors and the Assignor
         shall promptly comply with such request.

11.6     If the Security Trustee collects any Receivables pursuant to this
         Clause 11, it may take all measures and enter into all agreements with
         such Debtors which it considers to be expedient. In particular, the
         Security Trustee may grant discounts or indulgence to any Debtors
         and/or enter into settlement agreements in relation to existing
         receivables at any time.

11.7     With respect to the realisation of the Receivables, the Security
         Trustee will take into consideration the legitimate interests of the
         Assignor.

12.      LIMITATION OF SECURITY

12.1     The right to enforce the security interests created hereunder shall, to
         the extent that the Secured Obligations represent those of an
         affiliated company (verbundenes Unternehmen) within the meaning of
         Section 15 et seq. of the German Stock Corporation Act (Aktiengesetz)
         of the Assignor (other than any of the Assignor's subsidiaries), at all
         times be limited to an amount equal to the Assignor's assets (the
         calculation of which shall take into account the captions reflected in
         Section 266 sub-section (2) A, B and C of the German Commercial Code
         (Handelsgesetzbuch)) less the sum of (A) the Assignor's liabilities
         (the calculation of which shall take into account the captions
         reflected in Section 266 subsection (3) B, C and D of the German
         Commercial Code), and (B) the stated share capital (Stammkapital) of
         the Assignor (the "NET ASSETS").

12.2     The Assignor shall realise, to the extent legally permitted and, in
         respect of the Assignor, commercially justifiable, in a situation where
         the Assignor does not have sufficient Net Assets to maintain its
         registered share capital, any and all of its assets that are shown in
         the balance sheet with a book value (Buchwert) that is significantly
         lower than the market value of the assets if the asset is not necessary
         for the Assignor's business (betriebsnotwendig).

                                      - 9 -

<PAGE>

12.3     The Security Trustee shall enforce any security interest created
         hereunder against the Assignor in accordance with the following
         procedure:

                  (i)      The Assignor shall, following a notification by the
                           Security Trustee to the Assignor that an Enforcement
                           Event has occurred and that the Security Trustee
                           intends to enforce the security interests created
                           hereunder, deliver to the Security Trustee within
                           sixty days of such notification an auditors'
                           determination from a firm of auditors of
                           international standard and reputation (the "AUDITORS'
                           DETERMINATION") stating the value of the Net Assets,
                           i.e., the amounts which may be claimed against the
                           Assignor under the security interests created
                           hereunder having regard to Sections 30 and 31 of the
                           German Limited Liability Companies Act.

                  (ii)     The Auditors' Determination, i.e., the amount which
                           may be claimed against the Assignor under the
                           security interests created hereunder, having regard
                           to Section 30 and 31 of the German Limited Liability
                           Companies Act, shall take into account the generally
                           accepted accounting principles applicable from time
                           to time in Germany (GAAP) and be based on the same
                           principles that were applied when establishing the
                           previous year's balance sheet.

                  (iii)    The amount specified in the relevant Auditors'
                           Determination pertaining to the Assignor shall be
                           up-to-date and in any event such Auditors'
                           Determination shall have been prepared as of a date
                           no earlier than 15 business days prior to the date of
                           notification by the Security Trustee to the Assignor
                           that it intends to enforce the security interests
                           created hereunder.

                  (iv)     If the Assignor fails to deliver the Auditors'
                           Determination to the Security Trustee within the
                           sixty day period stated in (i) above, the Security
                           Trustee shall be entitled to enforce the security
                           interests created hereunder against the Assignor
                           without limitation.

13.      RELEASE (SICHERHEITENFREIGABE)

13.1     Upon complete and irrevocable satisfaction of the Secured Obligations,
         the Security Trustee shall (in accordance with the terms and subject to
         the conditions and circumstances set out in the Security Trust and
         Intercreditor Deed and without recourse to, or any representation or
         warranty by, the Security Trustee or any of its nominees) at the cost
         and expense of the Assignor reassign and/or transfer, as the

                                     - 10 -

<PAGE>

         case may require, to the Assignor, which shall accept such
         re-assignment and/or re-transfer, the Collateral and surrender the
         excess proceeds, if any, resulting from any realisation thereof. The
         Security Trustee will, however, transfer any Receivables to a third
         person if so required by law.

13.2     At any time when the total value of the aggregate security granted by
         the Assignor to secure the Secured Obligations (the "SECURITY") which
         can be expected to be realised in the event of an enforcement of the
         Security (realisierbarer Wert) exceeds 110% of the Secured Obligations
         (the "LIMIT") not only temporarily, the Security Trustee shall (in
         accordance with the terms and subject to the conditions and
         circumstances set out in the Security Trust and Intercreditor Deed and
         without recourse to, or any representation or warranty by, the Security
         Trustee or any of its nominees) on demand of the Assignor release such
         part of the Security (Sicherheitenfreigabe) as the Security Trustee may
         in its discretion determine so as to reduce the realisable value of the
         Security to the Limit.

14.      RIGHT OF INSPECTION

14.1     The Assignor undertakes to provide the Security Trustee promptly at its
         request with all information and documents which are necessary for
         perfecting and/or enforcing the security created hereby.

14.2     The Assignor authorises the Security Trustee during the term of this
         Agreement and upon notice to inspect its records during normal business
         hours, or to have them inspected by any one or more representatives,
         agents and advisors of the Security Trustee for the purpose of
         inspecting and checking any of the Collateral. Following an Event of
         Default, the Security Trustee may inspect such records at any time with
         or without prior notice.

15.      BOOKKEEPING AND DATA-PROCESSING

15.1     If proof or documents which are necessary to identify the Collateral
         have been handed over by the Assignor to a third party (in particular a
         bookkeeping firm or a tax consultant) the Assignor hereby transfers (on
         condition of (aufschiebende Bedingung) (i) the occurrence of an
         Insolvency Event of Default or (ii) notice by the Security Trustee if
         the Security Trustee has been so instructed pursuant to the Security
         Trust and Intercreditor Deed upon or at any time after the occurrence
         of an Event of Default which is continuing) to the Security Trustee,
         who accepts this transfer, its right to demand from such third party
         the return of the information and documents. The Assignor hereby
         undertakes to instruct the third party upon such transfer to provide
         the Security Trustee upon its demand with such information and

                                     - 11 -

<PAGE>

         documents which are necessary to perfect and/or enforce the security
         created hereby.

15.2     If details concerning the Collateral or any part thereof have been
         stored in an electronic data-processing system, then, upon the
         occurrence of an Insolvency Event of Default or upon request by the
         Security Trustee if the Security Trustee has been so instructed
         pursuant to the Security Trust and Intercreditor Deed upon or at any
         time after the occurrence of an Event of Default which is continuing,
         the Assignor shall allow the Security Trustee access to the computer,
         including the peripheral equipment and all data concerning the
         Collateral or such part thereof. Moreover, software operators shall be
         made available insofar as so required, and any assistance required
         shall be provided to the Security Trustee. If a third party handles the
         electronic processing of data, the Assignor hereby transfers (on
         condition of (aufschiebende Bedingung) (i) the occurrence of an
         Insolvency Event of Default or (ii) notice by the Security Trustee if
         the Security Trustee has been so instructed pursuant to the Security
         Trust and Intercreditor Deed upon or at any time after the occurrence
         of an Event of Default which is continuing) to the Security Trustee,
         who accepts this transfer, all rights against such third party relating
         to these services. The Assignor hereby undertakes to instruct the third
         party upon such transfer to handle the processing of data for the
         Security Trustee upon its demand as it did for the Assignor.

15.3     After transfer of the rights to the Security Trustee as contemplated in
         Clauses 15.1 and 15.2, the Security Trustee shall promptly upon request
         of the Assignor or after the Security Trustee receiving instructions
         pursuant to the Security Trust and Intercreditor Deed instruct the
         third party to provide the Assignor with such services and information
         as necessary for the Assignor in connection with the preparation and
         delivery of the Auditors' Determination.

16.      UNDERTAKINGS

         As far as necessary for the creation, perfection or maintenance of the
         security over the Collateral the Assignor undertakes to inform the
         Security Trustee promptly of any attachments (Pfandung) in respect of
         the Collateral or any part thereof. In the event of an attachment, the
         Assignor undertakes to forward to the Security Trustee upon request a
         copy of the attachment order (PfandungsbeschluB), the garnishee
         order (UberweisungsbeschluB) and all other documents necessary for
         a defence against the attachment. The Assignor shall inform the
         attaching creditor immediately of the Security Trustee's security
         interests.

                                     - 12 -

<PAGE>

17.      EXPENSES, COSTS AND TAXES

17.1     EXPENSES

         The Assignor shall, from time to time and promptly on demand by the
         Security Trustee reimburse to the Security Trustee all costs and
         expenses (including legal fees) on a full indemnity basis together with
         any applicable VAT incurred by the Security Trustee and any Delegate
         (provided that in relation to sub-clause (i) of this Clause 17, such
         costs and expenses must be properly incurred) in connection with:

                  (i)      the execution, release and discharge of this
                           Agreement and the security created or intended to be
                           created in respect of the Collateral and the
                           perfection of the security contemplated in this
                           Agreement or in any such documents or forming part of
                           the security created or intended to be created in
                           respect of the Collateral;

                  (ii)     the actual or contemplated exercise, preservation
                           and/or enforcement of any of the rights, powers and
                           remedies of, or the performance of the duties and
                           obligations of, the Security Trustee or any Delegate,
                           or any amendment or waiver in respect of this
                           Agreement;

                  (iii)    the foreclosure of any Collateral; and

                  (iv)     the preservation and/or enforcement of the security
                           created or intended to be created in respect of the
                           Collateral,

                  which shall carry interest (before and after any judgment and
                  to the extent interest at a default rate is not otherwise
                  being paid on such sum) from the date of such demand until so
                  reimbursed calculated on a daily basis at the rate determined
                  in accordance with the provisions of clause 18.4 (Interest on
                  Demands) of the Security Trust and Intercreditor Deed.

17.2     TAXES

         The Assignor shall pay, promptly on demand of the Security Trustee all
         stamp, registration, notarial and other similar Taxes or fees paid or
         payable by the Security Trustee in connection with any action taken or
         contemplated by or on behalf of the Security Trustee for perfecting,
         enforcing, releasing, cancelling, reassigning or resolving any doubt
         concerning, or for any other purpose in relation to this Agreement, any
         amendment thereto, any transfer and/or assignment of the rights and/or
         obligations under the same or the security created or intended to be
         created in respect of the Collateral and shall, from time to time,
         indemnify the Security

                                     - 13 -

<PAGE>

         Trustee promptly on demand against any liabilities, costs, claims and
         expenses resulting from any failure to pay by the Assignor or any delay
         by the Assignor in paying any such Taxes or fees.

18.      PARTIAL INVALIDITY; WAIVER

18.1     If at any time, any one or more of the provisions hereof is or becomes
         invalid, illegal or unenforceable in any respect under the law of any
         jurisdiction, that provision shall as to that jurisdiction be
         ineffective to the extent necessary without affecting or impairing the
         validity, legality and enforceability of the remaining provisions of
         this Agreement or of such provisions in any other jurisdiction. The
         invalid or unenforceable provision shall be deemed replaced by a valid,
         legal and enforceable provision which comes as close as possible to the
         original intent of the parties as to the invalid, illegal or
         unenforceable provision. This shall apply analogously in the case of
         gaps.

18.2     No failure to exercise, nor any delay in exercising, on the part of the
         Security Trustee, any right or remedy hereunder shall operate as a
         waiver thereof, nor shall any single or partial exercise of any right
         or remedy prevent any further or other exercise thereof or the exercise
         of any other right or remedy. The rights and remedies provided
         hereunder are cumulative and not exclusive of any rights or remedies
         provided by law.

19.      AMENDMENT; WAIVER

         This Agreement may be amended, modified or waived only in writing in an
         agreement signed by the Security Trustee. This also applies to this
         Clause 19.

20.      NOTICES AND THEIR LANGUAGE

20.1     Each communication under or in connection with this Agreement shall be
         made in writing and, unless otherwise stated, may be made by fax or
         letter.

20.2     Any communication or document to be made or delivered under or in
         connection with this Agreement shall be made or delivered to the
         following addresses or fax numbers (and for the attention of the
         department or officer noted):

         For the Assignor:            Marconi Communications GmbH
                                      Address:      GerberstraBe 33
                                                    D-71522 Backnang

                                      Fax:          07191 13 2419
                                      Attention:    Hans-Werner Altermann

                                     - 14 -

<PAGE>

                                                    Legal Advisor

         For the Security Trustee:    The Law Debenture Trust Corporation p.l.c.
                                      Address:      Fifth Floor
                                                    100 Wood Street
                                                    London EC2V 7EX
                                                    England

                                      Fax:          +44 20 7696 5261

                                      Attention:    Manager Trust Adminstration

         or to such other address as the recipient may notify or may have
         notified to the other party in writing.

20.3     DELIVERY

20.3.1   Any communication or document made or delivered by one person to
         another under or in connection with this Agreement will only be
         effective:

         (a)      if by way of fax, when received in legible form; or

         (b)      if by way of letter, when it has been left at the address
                  specified in Clause 20.2 above or five Business Days after
                  being deposited in the post postage prepaid in an envelope
                  addressed to the addressee at that address,

         and, if a particular department or officer is specified as part of that
         address, if addressed to that department or officer.

20.3.2   Notwithstanding the provisions of sub-clause 20.3.1 (b) above, any
         communication or document to be made or delivered to the Security
         Trustee will be effective only when actually received by the Security
         Trustee and then only if it is expressly marked for the attention of
         the department or officer identified in Clause 20.2 (or any substitute
         department or officer as such person shall specify for this purpose).

20.4     Any notice given under or connection with this Agreement shall be in
         the English language. All other documents provided under or in
         connection with this Agreement (other than copies to be provided
         pursuant to Clause 16.1) shall be in the English language or, if in any
         other language, accompanied by a translation into English which if
         reasonably requested by the Security Trustee shall be a certified
         translation. In the event of any conflict between the English text and
         the text in any

                                     - 15 -

<PAGE>

         other language, the English text shall prevail, unless the document is
         a constitutional, statutory or other official document.

21.      APPLICABLE LAW; JURISDICTION

21.1     APPLICABLE LAW

         This Agreement shall be governed by and construed in accordance with
         the laws of the Federal Republic of Germany.

21.2     GERMAN COURTS

         The courts of Frankfurt am Main have exclusive jurisdiction to settle
         any dispute (a "DISPUTE") arising out of or in connection with this
         Agreement (including a dispute regarding the existence, validity or
         termination of this Agreement or the consequences of its nullity).

21.3     CONVENIENT FORUM

         The parties agree that the court of Frankfurt am Main are the most
         appropriate and convenient court to settle Disputes between them and,
         accordingly, that they will not argue to the contrary.

21.4     NON-EXCLUSIVE JURISDICTION

         This Clause 21 is for the benefit of the Secured Creditors only. As a
         result it does not prevent any Secured Creditor from taking proceedings
         relating to a Dispute ("PROCEEDINGS") in any other courts with
         jurisdiction. To the extent allowed by law, the Secured Creditors may
         take concurrent Proceedings in any number of jurisdictions.

22.      ASSIGNMENT

         The Security Trustee may assign and transfer all or any of its rights
         and obligations under this Agreement in accordance with the Security
         Trust and Intercreditor Deed. To the extent legally permissible the
         Security Trustee shall be entitled to disclose such information
         concerning the Assignor and this Agreement as the Security Trustee
         considers appropriate to any actual or proposed direct or indirect
         successor or to any person to whom information may be required to be
         disclosed by any applicable law.

23.      EFFECTIVENESS

         This Agreement shall become effective only subject to the condition
         precedent and at the time of the first original issuance of the Senior
         Notes.

                                     - 16 -

<PAGE>

24.      COUNTERPARTS

         This Agreement may be executed in any number of counterparts and by
         different parties hereto on separate counterparts each of which, when
         executed and delivered, shall constitute an original, but all the
         counterparts shall together constitute but one and the same instrument.

                                     - 17 -

<PAGE>

                                   SCHEDULE 1
                               LIST OF RECEIVABLES

                                     - 18 -

<PAGE>

                                   SCHEDULE 2
                               LIST OF INSURANCES

n.a.

                                     - 19 -

<PAGE>

                                   SCHEDULE 3
                              FORM OF NOTIFICATION

To:           [Insurer]

Date:

Dear Sirs,

We hereby give you notice that pursuant to an assignment agreement entered into
by us in favour of The Law Debenture Trust Corporation p.l.c. (the "SECURITY
TRUSTEE") dated [ ] 2003 we have assigned all our right, title and interest in
and to all present and future claims against you in respect of [ ], details of
which are set out below, to the Security Trustee.

After your receipt of this notice:

(i)      all payments under or arising from the [  ] should be made to the
         Security Trustee into the following bank account: [bank account];

(ii)     all remedies [provided] for [in] the [  ] or available at law or in
         equity are exercisable by the Security Trustee;

(iii)    all rights to compel performance of the [  ] are exercisable by the
         Security Trustee;

(iv)     all rights, interests and benefits whatsoever accruing to or for the
         benefit of ourselves arising from the [  ] belong to the Security
         Trustee.

Please acknowledge receipt of this notice and declare your consent to the
assignment and the above terms by signing the acknowledgement on the enclosed
copy letter and returning the same to the Security Trustee at Fifth Floor, 100
Wood Street, London EC2V 7EX, England, attention: Manager Trust Administration.

Details of insurance policies

Date                      Parties                  Details of Insurance Policies

                                Yours faithfully,

                                     - 20 -

<PAGE>

                             _______________________
                              for and on behalf of
                        [insert name of relevant company]

                                     - 21 -

<PAGE>

                             FORM OF ACKNOWLEDGEMENT

                             [Letterhead of Insurer]

To:           The Law Debenture Trust Corporation p.l.c.

Copy:         [-]

Dear Sirs,

We refer to your letter of [  ] in which we are notified of an Assignment
Agreement dated [  ] under which [Assignor] has assigned to yourselves the
[description of all claims assigned] (the "ASSIGNED CLAIMS") together with all
rights pertaining thereto.

We confirm that we have not received notice of any previous arrangements or
changes of or over any of the Assigned Claims or any rights pertaining thereto.

We consent to the assignment and confirm that we shall make all payments in
respect of the Assigned Claims exclusively to the bank account as detailed in
the above mentioned letter or any other account as specified by you from time to
time and that we shall not exercise any right of combination, consolidation or
set off which we may have in respect of the Assigned Claims or any rights
pertaining thereto:

Yours faithfully

__________________________________________

[duly authorised signatory of the Insurer]

                                     - 22 -

<PAGE>

                                   SCHEDULE 4
                              FORM OF NOTIFICATION

To:           Debtor

Date:

Dear Sirs,

We hereby give you notice that pursuant to an assignment agreement entered into
by us in favour of The Law Debenture Trust Corporation p.l.c. (the "SECURITY
TRUSTEE") dated [-] 2003 we have assigned all our right, title and interest in
and to all present and future claims against you in respect of [-], details of
which are set out below, to the Security Trustee.

After your receipt of this notice:

(i)      all payments under or arising from the [  ] should be made to the
         Security Trustee into the follwing account [bank account];

(ii)     all remedies [provided] for [in] the [  ] or available at law or in
         equity are exercisable by the Security Trustee;

(iii)    all rights to compel performance of the [  ] are exercisable by the
         Security Trustee;

(iv)     all rights, interests and benefits whatsoever accruing to or for the
         benefit of ourselves arising from the [  ] belong to the Security
         Trustee.

Please acknowledge receipt of this notice and declare your consent to the
assignment and the above terms by signing the acknowledgement on the enclosed
copy letter and returning the same to the Security Trustee at Fifth Floor, 100
Wood Street, London EC2V 7EX, England, attention: Manager Trust Administration.

Details of the debt

Date                      Parties                  Details of Claims

                                Yours faithfully,

                                     - 23 -

<PAGE>

                             ______________________
                              for and on behalf of
                                       [-]

                             FORM OF ACKNOWLEDGEMENT

                             [Letterhead of Debtor]

To:           The Law Debenture Trust Corporation p.l.c.

Copy:         [-]

Dear Sirs,

We refer to your letter of [-] in which we are notified of an Assignment
Agreement dated [-] under which [Assignor] has assigned to yourselves the
[description of all claims assigned] (the "ASSIGNED CLAIMS") together with all
rights pertaining thereto.

We confirm that we have not received notice of any previous arrangements or
changes of or over any of the Assigned Claims or any rights pertaining thereto.

We consent to the assignment and confirm that we shall make all payments in
respect of the Assigned Claims exclusively to the bank account as detailed in
the above mentioned letter or any other account as specified by you from time to
time and that we shall not exercise any right of combination, consolidation or
set off which we may have in respect of the Assigned Claims or any rights
pertaining thereto:

Yours faithfully

___________________________________________

[duly authorised signatory of the Debtor]

                                     - 24 -

<PAGE>

                                   SCHEDULE 5
                                LIST OF ACCOUNTS

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------------
                                Account
Account Name                     Number     Swift Code    Currency      Bank Name            Address          Country
---------------------------------------------------------------------------------------------------------------------
<S>                           <C>           <C>           <C>        <C>              <C>                     <C>
Marconi Communications        75010413      BHFBDEFF600     EUR      BHF Bank AG      Th.-Heuss-Str. 21       Germany
GmbH                                                                                  70174 Stuttgart
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        7917917       COBADEFF602     EUR      Commerzbank AG   Ed.-Breuninger-Str. 2   Germany
GmbH                                                                                  71522 Backnang
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        7917917GBP    COBADEFF602     GBP      Commerzbank AG   Ed.-Breuninger-Str. 2   Germany
GmbH                                                                                  71522 Backnang
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        7917917USD    COBADEFF602     USD      Commerzbank AG   Ed.-Breuninger-Str. 2   Germany
GmbH                                                                                  71522 Backnang
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        7917917JPY    COBADEFF602     JPY      Commerzbank AG   Ed.-Breuninger-Str. 2   Germany
GmbH                                                                                  71522 Backnang
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        161722400     DEUTDESSXXX     EUR      DEUTSCHE BANK    Th.-Heuss-Str. 3        Germany
GmbH                                                                                  70174 Stuttgart
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        16172240003   DEUTDESSXXX     GBP      DEUTSCHE BANK    Th.-Heuss-Str. 3        Germany
GmbH                                                                                  70174 Stuttgart
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        16172240005   DEUTDESSXXX     USD      DEUTSCHE BANK    Th.-Heuss-Str. 3        Germany
GmbH                                                                                  70174 Stuttgart
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        16172240088   DEUTDESSXXX     JPY      DEUTSCHE BANK    Th.-Heuss-Str. 3        Germany
GmbH                                                                                  70174 Stuttgart
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        88778         SOLADES1WBN     EUR      Kreissparkasse   Am Obstmarkt 5          Germany
---------------------------------------------------------------------------------------------------------------------
</TABLE>

                                     - 25 -

<PAGE>
<TABLE>
<S>                           <C>           <C>           <C>        <C>              <C>                     <C>
---------------------------------------------------------------------------------------------------------------------
GmbH                                                                 Waiblingen       71522 Backnang
---------------------------------------------------------------------------------------------------------------------
Marconi Communications        4903323       SOLADES1WBN     EUR      Kreissparkasse   Am Obstmarkt 5          Germany
GmbH                                                                 Waiblingen       71522 Backnang
---------------------------------------------------------------------------------------------------------------------
</TABLE>

                                     - 26 -

<PAGE>

                                 SIGNATURE PAGE

THIS GLOBAL ASSIGNMENT AGREEMENT HAS BEEN ENTERED INTO ON THE DATE STATED AT THE
BEGINNING BY:

MARCONI COMMUNICATIONS GMBH

By:     MARY SKELLY
        Name:  Mary Skelly
        Title: Attorney

THE LAW DEBENTURE TRUST CORPORATION P.L.C.

By:     R. D. RANCE
        Name:  R. D. Rance
        Title: Director

                                     - 27 -