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                                                                    EXHIBIT 2.11

                             [LETTERHEAD OF COFIRI]


                                                           22nd December 1997



To:
Ansaldo Signal N.V.
Strawinskylaan 3051
1077 ZX Amsterdam
The Netherlands

Dear Sirs,

We are pleased to confirm that we are prepared to place the following facility
at your disposal on the terms and conditions contained herein.

1)       Lender

         Compagnia Finanziamenti e Rifinanziamenti - Cofiri SpA- Amsterdam
         Branch.

2)       Borrower

         Ansaldo Signal N.V.

3)       Amount

         The principal amount outstanding hereunder shall be USD 30,000,000 (the
         "Facility Amount")

4)       Drawings

         Upon the satisfaction of conditions contained in article 8) of this
         Agreement, the facility may be drawn down in one or more instalments
         (the "Advances"), by you giving us not less than two business days
         notice prior to the date on which the Advance is to be made (in this
         Facility Agreement, business day shall mean a day on which the London
         and New York financial markets are open for business and additionally,
         when a payment is to be effected, the banks in Amsterdam and in the
         centre where such payment is to be made are also open for business).
         The notice of drawing shall be confirmed immediately by telex and shall
         specify the amount of such Advance (not less than USD 10,000,000) and
         the first interest period selected, which may be of one, two, or three
         months and precise disposal instructions in respect thereof.

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5)       Interest and interest period

         Each Advance shall have successive interest periods. Each interest
         period for each Advance will commence on its Drawdown Date or on the
         expiry of the preceding interest period relative thereto. The Borrowers
         may select the duration of each interest period which may be of one,
         two, or three months, with three working days prior written notice. If
         the Borrower fails to select a duration for any interest period, such
         interest period shall be of one month. No interest period shall expire
         after June 30th, 1998. Interest will be calculated on each interest
         period at a rate per annum determined by the Lender to be the aggregate
         of (i) the margin of 1,00 per cent annum and (ii) the offered rate in
         the London Interbank Market (LIBOR) (rounded off to the fifth decimal,
         if necessary) for deposits in USD, for a duration equal to the length
         of the relevant interest period selected, at or about 11.00 a.m.
         (London time) on the second business day before the beginning of such
         interest period, as displayed on page "FRBD" on the Reuters Service (or
         such other page as may replace page "FRBD" on that service or such
         other service as may be nominated by the British Bankers' Association
         as the information vendor for the purpose of displaying British
         Bankers' Association Interest Settlements Rates for deposits in USD).
         Forthwith upon the determination by the Lender of the rate of interest
         applicable to any Interest Period the Lender shall notify the Borrower
         thereof and the certificate of the Lender as to the rate of interest
         applicable to any Interest Period shall be conclusive in the absence of
         manifest error. Interest will be payable, without deduction of any
         nature, at the end of each interest period.

         Interest will accrue on the actual number of days elapsed and shall be
         calculated on the basis of a year of 360 days.

         If any interest payment date would otherwise fall on a day which is not
         a business day in New York City, London or Amsterdam it shall be
         postponed to the next day which is a business day in New York City,
         London and Amsterdam.

6)       Payments

         All payments shall be made without set-off or counterclaim and free of
         and without deduction for any taxes, levies, imposts, duties, charges,
         fees, withholdings, restrictions or conditions of any nature. If at any
         time any applicable law, regulation or regulatory requirement of any
         governmental authority, monetary agency or central bank requires any
         such deduction to be made from any such payment, then the sum due from
         the Borrower to the Lender in respect of such payment shall be
         increased to the extent necessary to ensure that, after the making of
         such deduction, the Lender receives a net sum equal to the sum which it
         would have received had no such deduction required to be made.
         Furthermore, the Borrower will indemnify the Lender against any loss or
         cost incurred by reason of any failure on its part to make any such
         deduction or withholding.

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7)       Repayment

         Advances under the present Facility Agreement shall be repaid on the
         earlier of the two following dates:

         - the date on which the medium long term Facility of USD 80 million
         (see under clause 8 below) is drawn down,

         - June 30th, 1998.

8)       Condition Precedent

         The Facility under this Agreement shall become available to the
         Borrower upon receipt:

         a)       by the Lender of the copy of the present letter duly signed on
                  behalf of the Borrower for agreement;

         b)       by the Lender of a Comfort Letter - a copy of which is
                  attached hereto as Annex 1 - released by Ansaldo Trasporti
                  SpA; the Borrower shall provide the Lender with a Comfort
                  Letter - in the form attached hereto as Annex 2 - released by
                  Finmeccanica SpA;

         c)       by Cofiri SpA Rome of an irrevocable appointment as Arranger
                  for a 3/5 years committed Facility up to an aggregate amount
                  of USD 80 million, including a USD 60 million multicurrency
                  credit line and a line of USD 20 million for issuance of
                  stand-by and commercial letters of credit.

9)       Undertakings

         The Borrower undertakes with the Lender that, from the date of this
         Agreement and so long as any monies are owing thereunder, it will:

         a.       promptly inform the Lender of any occurrence of which it
                  becomes aware which might adversely affect its ability to
                  perform its obligations under this Agreement and, without
                  limiting the generality of the foregoing, will inform the
                  Lender of any Event of Default or any event which with the
                  giving of notice or lapse of time or both would constitute an
                  Event of Default forthwith upon becoming aware thereof;

         b.       send to the Lender a copy of every balance sheet, profit and
                  loss account, report, notice or public document of the kind,
                  in each case at the time of issue thereof or (in the case of
                  audited financial statements) as soon as practicable.

10)      Events of Default

         There shall be an Event of Default if:

         a.       the Borrower fails to pay any sum payable by it under this
                  Agreement on its due date; or

         b.       the Borrower commits any breach of or omits to observe any of
                  its obligations or undertakings under this Agreement (other
                  than failure to pay any sum when due) and in respect of any
                  such breach or omission which in the opinion of the Lender is
                  capable of remedy, such action as the Lender may require shall
                  not have been

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                  taken within 15 days of the Lender notifying the Borrower of
                  such default and of such required action; or

         c.       any representation or warranty made or deemed to be made by or
                  in respect of the Borrower pursuant to this Agreement or in
                  any notice, certificate or statement referred to in or
                  delivered under this Agreement is or proves to have been
                  incorrect in any material respect; or

         d.       any indebtedness of the Borrower is not paid when due or, by
                  reason of breach or default under the terms of any instrument
                  evidencing or guaranteeing the same on the part of the
                  Borrower, becomes due or capable of being declared due prior
                  to the date when it would otherwise have become due whether or
                  not such breach or default shall be waived by the person to
                  whom the same is payable, or any guarantee or indemnity given
                  by the Borrower in respect of indebtedness is not honoured
                  when due and called upon; or

         e.       the Borrower suspends or ceases or threatens to suspend or
                  cease to carry on its business as at the date of this
                  Agreement or enters into any unrelated business; or

         f.       any other event occurs or circumstance arises which, in the
                  opinion of the Lender, is likely materially and adversely to
                  affect the ability of the Borrower to perform all or any of
                  its respective obligations under or otherwise to comply with
                  the terms of this Agreement; or

         g.       it becomes unlawful for the Borrower to perform any or all of
                  its obligations under this Agreement; or

         h.       Ansaldo Trasporti SpA ceases to own (directly or indirectly)
                  at least 51% of the issued share capital of the Borrower.

         The Lender may, at any time after the occurrence of an Event of Default
         by notice to the Borrower declare that the Advances and all interest
         and all other sums payable under this Agreement have become due and
         payable, whereupon the same shall immediately, or in accordance with
         such notice, become due and payable.

11)      Indemnities

         The Borrower shall pay to the Lender on demand an amount sufficient to
         indemnify the Lender, without prejudice to any of its other rights
         under this Agreement, against any loss or expense which the Lender
         shall certify as sustained or incurred by it as a consequence of (i)
         any default in payment by the Borrower of any sum under this Agreement
         when due, (ii) the occurrence of any Event of Default.

         The Borrower shall pay all stamp, documentary, registration or other
         duties of the kind (including any duties payable by the Lender) imposed
         on or in connection with this Agreement and shall indemnify the Lender
         against any liability arising by reason of any delay or omission by the
         Borrower to pay such duties.

12)      Increased Costs

         If, by reason of (a) any change in law or in its interpretation or
         administration and/or (b)

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         compliance with any request from or requirement of any monetary of
         fiscal agency or central bank or authority of any nature without
         limitation, the Lender incurs a cost as a result of its having entered
         into and/or performing its obligations under this Agreement, then such
         increase in costs as the Lender shall certify to the Borrower shall be
         for the Borrower's account.

         The Lender will forthwith, after having been aware of such costs,
         advise the Borrower of the application of any such increase.

         The Lender retains the option, in the occurrence of any of the above
         and upon its first written demand, to request the repayment of the full
         amount of the principal, interest and any other cost incurred by us
         under the Facility.

13)      Law and jurisdiction

         This Agreement shall be governed by and construed in accordance with
         the laws of the Netherlands.

         Nothing contained in this Clause shall limit the right of the Lender to
         take proceedings against the Borrower in any other court of competent
         jurisdiction, nor shall the taking of proceedings in any one or more
         jurisdictions preclude the taking of proceedings in any other
         jurisdiction, whether concurrently or not.

14)      Miscellaneous

         Every notice, request, demand or other communication shall be sent:

         1.       to the Borrower at:
                  Ansaldo Signal N.V.
                  Strawinskylaan 3051
                  1077 ZX Amsterdam

         2.       to the Lender at:
                  Cofiri SpA
                  Amsterdam Branch
                  Strawinskylaan 3105 7th floor
                  1077 ZX Amsterdam

         or such other address or telex number as is notified by one party to
         the other party under this Agreement.

         No failure or delay on the part of the Lender to exercise any power,
         right or remedy under this Agreement shall operate as a waiver thereof,
         nor shall any single or partial exercise by the Lender of any power,
         right or remedy preclude any other or further exercise thereof or the
         exercise of any other power, right or remedy. The remedies provided in

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         this Agreement are cumulative and are not exclusive of any remedies
         provided by law.

         All certificates, instruments and other documents to be delivered under
         or supplied in connection with this Agreement shall be in English or
         Italian.

         No amendment to this Agreement shall be effective unless and until made
         in writing and signed by the Lender and the Borrower.



         Yours faithfully;

         Agreed by Ansaldo Signal N.V.:        COMPAGNIA FINANZIAMENTI E
                                               RIFINANZIAMENTI COFIRI SpA
                                               Amsterdam Branch


         /s/James Sanders                      /s/ Illegible


                                               ABM Trustcompany (Nederland) B.V.

                                               /s/ Illegible
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                             [Letterhead of COFIRI]


                                                                   23 April 1998
                                                                         0528/CH

Ansaldo Signal N.V.
Schiphol Boulevard 267
1118 DW Schiphol
The Netherlands

Re:      USD 30,000,000 Credit Facility Agreement (the "Loan Agreement") dated
         22nd December 1997; Ansaldo Signal N.V. - Borrower; Cofiri S.p.A.
         Amsterdam Branch
- Lender

Dear Sirs:

With reference to the captioned Facility and following your letter dated 7th
April 1998, we are pleased to confirm you that the "Facility Amount", as defined
in Clause 3 of the Loan Agreement, is increased from USD 30 million to USD 50
million, subject to receipt by the Lender of:

a)       a copy of this letter duly signed by the Borrower;

b)       a letter of Acknowledgment released by Ansaldo Trasporti S.p.A., in the
         form attached hereto as annex 1.

All other terms and conditions stated in the Loan Agreement remain in full force
and effect.

Yours faithfully,


COMPAGNIA FINANZIAMENTI                        ABN Trustcompany (Nederland) B.V.
E REFINANZIAMENTI COFIRI S.p.A.
Amsterdam Branch

/s/ Illegible                                  /s/ Illegible



Encl.                                          /s/ James N. Sanders
                                                          23/4/98