Document:

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                                                                  Exhibit 10.25

                                PROMISSORY NOTE
                                ---------------

$206,500                                                          23 March 2000

     FOR VALUE RECEIVED, the undersigned, MARTIN RUSHE ("Maker"), promises to
pay to the order of IPCENTA LIMITED, a limited company organized under the laws
of England and Wales (together with any subsequent holder hereof, "Payee"), the
sum of TWO HUNDRED SIX THOUSAND FIVE HUNDRED DOLLARS ($206,500), (the "Principal
Balance"), together with interest on the unpaid Principal Balance at the rate of
seven percent (7%) compounded at half-yearly intervals calculated from January
15, 2000.

     The entire unpaid Principal Balance of this Promissory Note (this "Note")
together with all accrued but unpaid interest and all other amounts due from
Maker will be due and payable in full on the earlier of (the "Maturity Date"):
(i) January 15, 2003, or (ii) the date which is thirty (30) days after the date
on which Maker's employment with Payee or an Affiliate employing Payee
terminates as a result of a Termination For Cause, or (iii) the date which is
ninety (90) days after the date on which Maker's employment with Payee or an
Affiliate employing Payee terminates as a result of a Voluntary Termination.
Maker may prepay this Note, in any amount, at any time and from time to time,
without penalty.  All payments made under this Note must be made in legal tender
of the United States of America to Payee at Payee's principal place of business
or at such other place as the holder of this Note designates in writing.

     As used herein, the following terms have the following meanings:

          "Affiliate" of any particular Person means (i) any other Person
controlling, controlled by or under common control with such particular Person,
where "control" means the possession, directly or indirectly, of the power to
direct the management and policies of a Person, whether through the ownership of
shares, by contract or otherwise, and (ii) if such Person is a partnership, any
partner thereof.

          "CompleTel UK Limited Employment Agreement" means the employment
agreement to be dated January 24, 2000 by and between Maker and CompleTel UK
Limited, as amended from time to time in accordance with the provisions thereof.

          "Executive Agreement" means the Amended and Restated Executive
Securities Agreement dated as of the date hereof by and between CompleTel LLC
and Maker.

          "Termination For Cause" means (i) termination of Maker's appointment
as President of CompleTel UK Limited pursuant to Section 5.1 of the CompleTel UK
Limited Employment Agreement and (ii) termination of Maker's appointment as
President of CompleTel UK Limited for "Cause" as such term is defined in the
Executive Agreement.

          "Voluntary Termination" means any termination of Maker's appointment
as President of CompleTel UK Limited other than Termination for Cause.
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     This Note is secured by Maker's interest in the common units of CompleTel
LLC (the "Collateral") issued to Maker pursuant to the Executive Agreement.
Maker covenants and agrees that he will not pledge or otherwise encumber or
grant a security interest in the Collateral to any other party while any
indebtedness represented by this Note remains unpaid and outstanding.

     Whenever Payee sustains or incurs any losses or out-of-pocket expenses with
respect to this Note in connection with (i) repayment of overdue amounts under
this Note, or (ii) failure by Maker to pay all principal and interest on this
Note, when due hereunder (whether at maturity, by reason of acceleration, or
otherwise), Maker will pay, on demand, to Payee, in addition to any other
penalties or premiums hereunder, an amount sufficient to compensate Payee for
all such losses or out-of-pocket expenses, including, without limitation, all
costs and expenses of a suit or proceeding (or any appeal thereof) brought for
recovery of all or any part of or for protection of the indebtedness evidenced
by this Note or to enforce Payee's rights hereunder, including reasonable legal
fees and expenses.

     Maker acknowledges and agrees that Payee is entitled to setoff any amounts
owed or distributable by Payee or any of its Affiliates to Maker against any
amounts that are due and owing from Maker to Payee hereunder.

     Time is of the essence hereof.  At the option of Payee, payment of the
Principal Balance and any and all accrued interest thereon may be accelerated,
and such amounts will be immediately due and payable without further notice or
demand upon the occurrence of any of the following events (each an "Event of
Default"):

     (1) Maker's failure to make any payment of any and all amounts required to
be paid hereunder when due or declared due.

     (2) The occurrence of any default by Maker or event of default under any
other documents executed in connection herewith.

     Unpaid principal and interest due and payable hereunder not paid when due
or declared due hereunder will bear interest at the rate of 10% per annum until
paid.

     The remedies provided in this Note will be cumulative, and will be in
addition to any other rights or remedies now or hereafter provided by law or
equity.  No delay, failure or omission by any holder of this Note, in respect of
any default by Maker, to exercise any right or remedy will constitute a waiver
of the right to exercise the right or remedy upon any such default or subsequent
default.

     Maker and any endorser herein waives presentment, demand, notice of
dishonor, notice of acceleration and protest and assents to any extension of
time with respect to any payment due under this Note, to any substitution or
release of security and to the addition or release of any party.  No waiver of
any payment or other right under this Note will operate as a waiver of any other
payment or right.

                                       2
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     This Note may not be changed orally, but only by an agreement in writing,
signed by the party against whom enforcement of any waiver, change, modification
or discharge is sought.

     If any provision of this Note is held to be invalid or unenforceable, the
determination of invalidity or unenforceability of such provision will not
affect the validity or enforceability of any other provision or provisions
hereof.

     This Note will be binding upon Maker and its successors and assigns and
will inure to the benefit of and be enforceable by Payee and its successors and
assigns.

     This Note will be governed by, and construed and enforced in accordance
with English law.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                       3
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     IN WITNESS WHEREOF, Maker has caused this instrument to be executed as of
the day and year first above written.

/s/ Martin Rushe
--------------------------------
Martin Rushe

SIGNED and DELIVERED
by MARTIN RUSHE as his
Deed in the presence of:

WITNESS

Signature:  /s/ David Lacey
            ---------------------------
Name:       David Lacey
            ---------------------------
Address:    6300 S. Syracuse, Suite 355
            Englewood, CO 80111
            ---------------------------

                                       4<PAGE>

                                                                  Exhibit 10.26

                                IPCENTA LIMITED
                  The Pall Mall Deposit, 124-128 Barlby Road
                    London W10 6BL, Phone: 44 1181 962 3200

March 23, 2000

Martin Rushe
c/o iPcenta Limited
The Pall Mall Deposit
124-128 Barlby Road
London W10 6BL
Phone: 44 1181 962 3200

RE:  Purchase of 100 Common Units of CompleTel, LLC

Dear Mr. Rushe:

This letter is delivered in connection with the purchase by you, Martin Rushe
("Rushe") of 100 common units (the "Units") of CompleTel LLC ("CompleTel") at a
per unit price of US$2,065 and an aggregate price of US$206,500.  IPcenta
Limited ("iPcenta") has agreed to loan you the purchase price in exchange for a
promissory note dated as of March 23, 2000, but effective from January 15, 2000
(the "Note").  The purpose of this Letter is to set forth the understandings
among you, CompleTel and iPcenta concerning the forgiveness of principal and
accrued interest on the Note.

In connection with the foregoing, the parties agree as follows:

     1.   At such time as ownership of any of the Units vest pursuant to the
vesting provisions contained in the Amended and Restated Executive Securities
Agreement and the Second Amended and Restated Performance Vesting Agreement, or
any successor vesting agreement (the "Vesting Agreements"), iPcenta agrees to
forgive a pro rata percentage of principal and accrued interest under the Note.

     2.   At such time as ownership of any of the Units are forfeited under the
Vesting Agreements, a pro rata percentage of principal and accrued interest
under the Note will become due and payable; provided, however, that such
obligation will be satisfied in full by CompleTel repurchasing such forfeited
Units pursuant to the Vesting Agreements and paying the repurchase price
directly to iPcenta.

     3.   IPcenta agrees to reimburse Rushe for any and all taxes incurred by
him as a result of iPcenta forgiving any principal and accrued interest under
the
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Martin Rushe
March 23, 2000
Page 2

Note. IPcenta's intention is that Rushe shall be held fully harmless from any
additional taxes of any kind associated with such loan forgiveness.

Please indicate your acceptance of this agreement by signing below.

Very truly yours,

IPCENTA LIMITED

By:   /s/ James E. Dovey
   ---------------------------
     James E. Dovey, Director

Accepted and agreed to as of the date first written above:

                              COMPLETEL LLC

/s/ Martin Rushe              /s/ William H. Pearson
-----------------------       ----------------------------
Martin Rushe                  William H. Pearson
                              President and CEO

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