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                                                                    EXHIBIT 10.8

                 AMENDED AND RESTATED UNCONDITIONAL GUARANTY OF
                             PAYMENT AND PERFORMANCE

         FOR AND IN CONSIDERATION OF the sum of Ten and No/100 Dollars ($10.00)
and other good and valuable consideration paid or delivered to the undersigned
NEW PLAN EXCEL REALTY TRUST, INC., a Maryland corporation, formerly known as
Excel Realty Trust, Inc. (hereinafter referred to as "Guarantor"), the receipt
and sufficiency whereof are hereby acknowledged by Guarantor, and for the
purpose of seeking to induce FLEET NATIONAL BANK (formerly known as BankBoston,
N.A.), a national banking association (hereinafter referred to as "Lender",
which term shall also include each other Bank which may now or hereafter become
party to the "Loan Agreement" (as hereinafter defined) and shall also include
Fleet National Bank, as agent for all of the Banks, and any other Bank that is
hereafter acting as agent for all of the Banks), to extend credit or otherwise
provide financial accommodations to BRIAR PRESTON RIDGE PARTNERS, L.P., a Texas
limited partnership (hereinafter referred to as "Borrower"), which extension of
credit and provision of financial accommodations will be to the direct interest,
advantage and benefit of Guarantor, Guarantor does hereby absolutely,
unconditionally and irrevocably guarantee to Lender:

         (a) the full and prompt payment when due, whether by acceleration or
otherwise, either before or after maturity thereof, of that certain Amended and
Restated Note (hereinafter referred to as the "Fleet Note"), dated as of April
___, 2000, made by Borrower to the order of Fleet in the principal face amount
of TWENTY-SIX MILLION EIGHT HUNDRED THOUSAND AND NO/100 DOLLARS
($26,800,000.00), together with interest as provided in the Fleet Note, together
with any replacements, supplements, renewals, modifications, consolidations,
restatements and extensions thereof; and

         (b) the full and prompt payment when due, whether by acceleration or
otherwise, either before or after maturity thereof, of each other note as may be
issued under that certain Second Amended and Restated Term Loan Agreement, dated
as of April ___, 2000 (hereinafter referred to as the "Loan Agreement") among
Borrower, Fleet, for itself and as Agent, and the other Banks that may become a
party thereto, together with interest as provided in each such note, together
with any replacements, supplements, renewals, modifications, consolidations,
restatements and extensions thereof (the Fleet Note and each of the notes
described in this subparagraph (b) is hereinafter referred to collectively as
the "Note"); and

         (c) the full and prompt payment and performance of all obligations of
Borrower to Lender under the terms of the Loan Agreement, together with any
replacements, supplements, renewals, modifications, consolidations, restatements
and extensions thereof; and

         (d) the full and prompt payment and performance of any and all
obligations of Borrower under the terms of the "Deed of Trust" (as defined in
the Loan Agreement) from Borrower relating to certain real property more
particularly described therein (such real property is hereinafter referred to as
the "Land"), together with any replacements, supplements, renewals,
modifications, consolidations, restatements and extensions thereof, including,
without limitation,
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the obligations of Borrower concerning hazardous materials contained in
paragraph 7 of the Deed of Trust; and

         (e) the full and prompt payment and performance of any and all other
obligations of Borrower to Lender under any other agreements, documents or
instruments now or hereafter evidencing, securing or otherwise relating to the
indebtedness evidenced by the Note or the Loan Agreement (the Note, the Loan
Agreement, the Deed of Trust and said other agreements, documents and
instruments are hereinafter collectively referred to as the "Loan Documents" and
individually referred to as a "Loan Document").

         All terms used herein and not otherwise defined herein shall have the
meanings set forth in the Loan Agreement. This Guaranty is executed and
delivered by Guarantor in amendment and restatement of that certain
Unconditional Guaranty of Payment and Performance dated as of December 30, 1997,
made by Excel Realty Trust, Inc. in favor of Lender, and in amendment and
restatement of that certain Unconditional Guaranty of Payment and Performance
dated as of December 30, 1998, made by New Plan Excel Realty Trust, Inc. in
favor of Lender, and in amendment and restatement of that certain Unconditional
Guaranty of Payment and Performance dated as of January 13, 1999, made by New
Plan Excel Realty Trust, Inc. in favor of Lender.

         1. Agreement to Pay and Perform; Costs of Collection. Guarantor does
hereby agree that if the Note is not paid by Borrower in accordance with its
terms, or if any and all sums which are now or may hereafter become due from
Borrower to Lender under the Loan Documents are not paid by Borrower in
accordance with their terms, or if any and all other obligations of Borrower to
Lender under the Note and the Loan Documents are not performed by Borrower in
accordance with their terms, Guarantor will immediately make such payments and
perform such obligations. Guarantor further agrees to pay Lender on demand all
reasonable costs and expenses (including court costs and reasonable attorneys'
fees and disbursements) paid or incurred by Lender in endeavoring to collect the
indebtedness guaranteed hereby, to enforce any of the other obligations of
Borrower guaranteed hereby, or any portion thereof, or to enforce this Guaranty,
and until paid to Lender, such sums shall bear interest at the default rate of
interest provided in the Loan Agreement unless collection from Guarantor of
interest at such rate would be contrary to applicable law, in which event such
sums shall bear interest at the highest rate which may be collected from
Guarantor under applicable law.

         2. Reinstatement of Refunded Payments. If, for any reason, any payment
to Lender of any of the obligations guaranteed hereunder is required to be
refunded by Lender to Borrower, or paid or turned over to any other person,
including, without limitation, by reason of the operation of bankruptcy,
reorganization, receivership or insolvency laws or similar laws of general
application relating to creditors' rights and remedies now or hereafter enacted,
Guarantor agrees to pay the amount so required to be refunded, paid or turned
over (the "Turnover Payment"), and the obligations of Guarantor shall not be
treated as having been discharged by the original payment to Lender giving rise
to the Turnover Payment, and this Guaranty shall be treated as having remained
in full force and effect for any such Turnover Payment so made by Lender, as
well as for any amounts not theretofore paid to Lender on account of such
obligations.
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         3. Rights of Lender to Deal with Collateral, Borrower and Other
Persons. Guarantor hereby consents and agrees that Lender may at any time, and
from time to time, without thereby releasing Guarantor from any liability
hereunder and without notice to or further consent from Guarantor, either with
or without consideration: release or surrender any lien or other security of any
kind or nature whatsoever held by it or by any person, firm or corporation on
its behalf or for its account, securing any indebtedness or liability hereby
guaranteed; substitute for any collateral so held by it, other collateral of
like kind, or of any kind; modify the terms of the Note or the Loan Documents;
extend or renew the Note for any period; grant releases, compromises and
indulgences with respect to the Note or the Loan Documents and to any persons or
entities now or hereafter liable thereunder or hereunder; release any other
Guarantor, surety, endorser or accommodation party of the Note, the Security
Deed or any other Loan Documents; or take or fail to take any action of any type
whatsoever. No such action which Lender shall take or fail to take in connection
with the Note or the Loan Documents, or any of them, or any security for the
payment of the indebtedness of Borrower to Lender or for the performance of any
obligations or undertakings of Borrower, nor any course of dealing with Borrower
or any other person, shall release Guarantor's obligations hereunder, affect
this Guaranty in any way or afford Guarantor any recourse against Lender. The
provisions of this Guaranty shall extend and be applicable to all replacements,
supplements, renewals, amendments, extensions, consolidations, restatements and
modifications of the Note and the Loan Documents, and any and all references
herein to the Note and the Loan Documents shall be deemed to include any such
replacements, supplements, renewals, extensions, amendments, consolidations,
restatements or modifications thereof.

         4. No Contest with Lender; Subordination. So long as any obligation
hereby guaranteed remains unpaid or undischarged, Guarantor will not, by paying
any sum recoverable hereunder (whether or not demanded by Lender) or by any
means or on any other ground, claim any set-off or counterclaim against Borrower
in respect of any liability of Guarantor to Borrower or, in proceedings under
federal bankruptcy law or insolvency proceedings of any nature, prove in
competition with Lender in respect of any payment hereunder or be entitled to
have the benefit of any counterclaim or proof of claim or dividend or payment by
or on behalf of Borrower or the benefit of any other security for any obligation
hereby guaranteed which, now or hereafter, Lender may hold or in which it may
have any share. So long as any obligation hereby guaranteed remains unpaid or
undischarged, Guarantor hereby expressly waives any right of contribution from
or indemnity against Borrower, whether at law or in equity, arising from any
payments made by Guarantor pursuant to the terms of this Guaranty, and Guarantor
acknowledges that Guarantor has no right whatsoever to proceed against Borrower
for reimbursement of any such payments. In connection with the foregoing,
Guarantor expressly waives any and all rights of subrogation to Lender against
Borrower, and Guarantor hereby waives any rights to enforce any remedy which
Lender may have against Borrower and any rights to participate in any collateral
for Borrower's obligations under the Loan Documents. Guarantor hereby
subordinates any and all indebtedness of Borrower now or hereafter owed to
Guarantor to all indebtedness of Borrower to Lender, and agrees with Lender that
(a) Guarantor shall not demand or accept any payment from Borrower on account of
such indebtedness, unless such payment is approved by Lender in the exercise of
its sole discretion, (b) Guarantor shall not claim any offset or other reduction
of
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Guarantor's obligations hereunder because of any such indebtedness, and (c)
Guarantor shall not take any action to obtain any interest in any of the
security described in and encumbered by the Loan Documents because of any such
indebtedness; provided, however, that, if Lender so requests, such indebtedness
shall be collected, enforced and received by Guarantor as trustee for Lender and
be paid over to Lender on account of the indebtedness of Borrower to Lender, but
without reducing or affecting in any manner the liability of Guarantor under the
other provisions of this Guaranty except to the extent the principal amount of
such outstanding indebtedness shall have been reduced by such payment.

         5. Waiver of Defenses. Guarantor hereby agrees that its obligations
hereunder shall not be affected or impaired by, and hereby waives and agrees not
to assert or take advantage of any defense based on:

            (a) any statute of limitations in any action hereunder or for the
collection of the Note or for the payment or performance of any obligation
hereby guaranteed;

            (b) the incapacity, lack of authority, death or disability of
Borrower or any other person or entity, or the failure of Lender to file or
enforce a claim against the estate (either in administration, bankruptcy or in
any other proceeding) of Borrower or Guarantor or any other person or entity;

            (c) the dissolution or termination of existence of Borrower or
Guarantor;

            (d) the voluntary or involuntary liquidation, sale or other
disposition of all or substantially all of the assets of Borrower;

            (e) the voluntary or involuntary receivership, insolvency,
bankruptcy, assignment for the benefit of creditors, reorganization, assignment,
composition, or readjustment of, or any similar proceeding affecting, Borrower
or Guarantor, or any of Borrower's or Guarantor's properties or assets;

            (f) the damage, destruction, condemnation, foreclosure or surrender
of all or any part of the Land or any improvements now or hereafter located on
the Land (the "Improvements");

            (g) any change in the plans and specifications relating to the
construction of the Improvements;

            (h) any modification of the terms of any contract relating to the
construction of the Improvements or the furnishing of any labor, equipment,
supplies or materials therefor;

            (i) the failure of Lender to give notice of the existence, creation
or incurring of any new or additional indebtedness or obligation or of any
action or nonaction on the part of any other person whomsoever in connection
with any obligation hereby guaranteed;
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            (j) any failure or delay of Lender to commence an action against
Borrower or any other Person, to assert or enforce any remedies against Borrower
under the Note or the Loan Documents, or to realize upon any security;

            (k) any failure of any duty on the part of Lender to disclose to
Guarantor any facts it may now or hereafter know regarding Borrower, the Land or
any of the Improvements, whether such facts materially increase the risk to
Guarantor or not;

            (l) failure to accept or give notice of acceptance of this Guaranty
by Lender;

            (m) failure to make or give notice of presentment and demand for
payment of any of the indebtedness or performance of any of the obligations
hereby guaranteed;

            (n) failure to make or give protest and notice of dishonor or of
default to Guarantor or to any other party with respect to the indebtedness or
performance of obligations hereby guaranteed;

            (o) any and all other notices whatsoever to which Guarantor might
otherwise be entitled;

            (p) any lack of diligence by Lender in collection, protection or
realization upon any collateral securing the payment of the indebtedness or
performance of obligations hereby guaranteed;

            (q) the invalidity or unenforceability of the Note or any of the
Loan Documents;

            (r) the compromise, settlement, release or termination of any or all
of the obligations of Borrower under the Note or the Loan Documents;

            (s) any transfer by Borrower or any other Person of all or any part
of the security encumbered by the Loan Documents;

            (t) any exculpation or limitation of liability contained in the Note
or in the Loan Documents;

            (u) the failure of Lender to perfect any security or to extend or
renew the perfection of any security;

            (v) the failure of Guarantor to receive payment of any fees or other
sums at any time payable by Borrower or any other person in connection with the
execution and delivery by Guarantor of the Guaranty or in connection with the
ownership, development or operation of the Land or any Improvements; or

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            (w) to the fullest extent permitted by law, any other legal,
equitable or surety defenses whatsoever to which Guarantor might otherwise be
entitled, it being the intention that the obligations of Guarantor hereunder are
absolute, unconditional and irrevocable.

         6. Guaranty of Payment and Performance and Not of Collection. This is a
Guaranty of payment and performance and not of collection. The liability of
Guarantor under this Guaranty shall be primary, direct and immediate and not
conditional or contingent upon the pursuit of any remedies against Borrower or
any other person, nor against securities or liens available to Lender, its
successors, successors in title, endorsees or assigns. Guarantor hereby waives
any right to require that an action be brought against Borrower or any other
person or to require that resort be had to any security or to any balance of any
deposit account or credit on the books of Lender in favor of Borrower or any
other person.

         7. Rights and Remedies of Lender. In the event of a default under the
Note or the Loan Documents, or any of them, Lender shall have the right to
enforce its rights, powers and remedies thereunder or hereunder or under any
other agreement, document or instrument now or hereafter evidencing, securing or
otherwise relating to the indebtedness evidenced by the Note or secured by the
Loan Documents, in any order, and all rights, powers and remedies available to
Lender in such event shall be nonexclusive and cumulative of all other rights,
powers and remedies provided thereunder or hereunder or by law or in equity.
Accordingly, Guarantor hereby authorizes and empowers Lender upon the occurrence
of any event of default under the Note or the Loan Documents, at its sole
discretion, and without notice to Guarantor, to exercise any right or remedy
which Lender may have, including, but not limited to, judicial foreclosure,
exercise of rights of power of sale, acceptance of a deed or assignment in lieu
of foreclosure, appointment of a receiver to collect rents and profits, exercise
of remedies against personal property, or enforcement of any assignment of
leases, as to any security, whether real, personal or intangible. At any public
or private sale of any security or collateral for any indebtedness or any part
thereof guaranteed hereby, whether by foreclosure or otherwise, Lender may, in
its discretion, purchase all or any part of such security or collateral so sold
or offered for sale for its own account and may apply against the amount bid
therefor all or any part of the balance due it pursuant to the terms of the Note
or Security Deed or any other Loan Document without prejudice to Lender's
remedies hereunder against Guarantor for deficiencies. If the indebtedness
guaranteed hereby is partially paid by reason of the election of Lender to
pursue any of the remedies available to Lender, or if such indebtedness is
otherwise partially paid, this Guaranty shall nevertheless remain in full force
and effect, and Guarantor shall remain liable for the entire balance of the
indebtedness guaranteed hereby even though any rights which Guarantor may have
against Borrower may be destroyed or diminished by the exercise of any such
remedy.

         8. Application of Payments. Guarantor hereby authorizes Lender, without
notice to Guarantor, to apply all payments and credits received from Borrower or
from Guarantor or realized from any security in such manner and in such priority
as Lender in its sole judgment shall see fit to the indebtedness, obligation and
undertakings which are the subject of this Guaranty.

         9. Business Failure, Bankruptcy or Insolvency. In the event of the
business failure
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of Guarantor or if there shall be pending any bankruptcy or insolvency case or
proceeding with respect to Guarantor under federal bankruptcy law or any other
applicable law or in connection with the insolvency of Guarantor, or if a
liquidator, receiver, or trustee shall have been appointed for Guarantor or
Guarantor's properties or assets, Lender may file such proofs of claim and other
papers or documents as may be necessary or advisable in order to have the claims
of Lender allowed in any proceedings relative to Guarantor, or any of
Guarantor's properties or assets, and, irrespective of whether the indebtedness
or other obligations of Borrower guaranteed hereby shall then be due and
payable, by declaration or otherwise, Lender shall be entitled and empowered to
file and prove a claim for the whole amount of any sums or sums owing with
respect to the indebtedness or other obligations of Borrower guaranteed hereby,
and to collect and receive any moneys or other property payable or deliverable
on any such claim. Guarantor covenants and agrees that upon the commencement of
a voluntary or involuntary bankruptcy proceeding by or against Borrower,
Guarantor shall not seek a supplemental stay or otherwise pursuant to 11 U.S.C.
ss.105 or any other provision of the Bankruptcy Reform Act of 1978, as amended,
or any other debtor relief law (whether statutory, common law, case law, or
otherwise) of any jurisdiction whatsoever, now or hereafter in effect, which may
be or become applicable, to stay, interdict, condition, reduce or inhibit the
ability of Lender to enforce any rights of Lender against Guarantor by virtue of
this Guaranty or otherwise.

         10. Financial Statements and Other Information. Guarantor hereby
represents and warrants to Lender that all financial statements of Guarantor and
its subsidiaries heretofore delivered by Guarantor to Lender are true and
correct in all material respects, have been prepared in accordance with
generally accepted accounting principles consistently applied, and fairly
present the financial condition of Guarantor as at the close of business on the
date thereof and the results of operations for the period then ended; that no
material adverse change has occurred in the assets, liabilities, financial
condition or business of Guarantor as shown or reflected therein since the date
thereof; and that Guarantor and its subsidiaries have no liabilities or known
contingent liabilities which are not reflected in such financial statements or
referred to in the notes thereto other than Guarantor's obligations under this
Guaranty. Guarantor hereby agrees that until all indebtedness guaranteed hereby
has been completely repaid and all obligations and undertakings of Borrower
under, by reason of, or pursuant to the Note and the Loan Documents have been
completely performed, Guarantor will deliver to Lender:

            (a) as soon as practicable and in any event within 90 days after the
end of each fiscal year of Guarantor, the consolidated balance sheet of
Guarantor and its subsidiaries as of the end of such year (accompanied by
supplementary schedules indicating the total debt on any assets shown on a net
investment basis), and the related statement of income, statement of changes in
capital and statement of cash flows for such year, each setting forth in
comparative form the figures for the previous fiscal year and all such
statements to be in reasonable detail, prepared in accordance with generally
accepted accounting principles, and accompanied by an auditor's report prepared
without qualification by an accounting firm acceptable to Lender, the Form 10-K
filed with the federal Securities and Exchange Commission ("SEC") (unless the
SEC has approved an extension, in which event the Guarantor will deliver to each
Lender a copy of the Form 10-K simultaneously with delivery to the SEC), and any
other information the Lender
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reasonably may need to complete a financial analysis of Guarantor;

            (b) as soon as practicable and in any event within 45 days after the
end of each of the fiscal quarters of Guarantor (including the fourth fiscal
quarter in each year), copies of Form 10-Q filed with the SEC (unless the SEC
has approved an extension in which event the Guarantor will deliver such copies
of the Form 10-Q to each Lender simultaneously with delivery to the SEC); the
unaudited consolidated balance sheet of Guarantor and its subsidiaries as of the
end of such quarter, and the related statement of income, statement of changes
in capital and statement of cash flows for the portion of Guarantor's fiscal
year then elapsed, and any compliance certificate required to be delivered to
the agent and/or the lenders pursuant to any Credit Agreement, all in reasonable
detail and prepared in accordance with generally accepted accounting principles,
together with a certification by the principal financial or accounting officer
of Guarantor that the information contained in such financial statements fairly
presents the financial position of Guarantor and its subsidiaries on the date
thereof (subject to year end adjustment);

            (c) contemporaneously with the delivery of the financial statements
referred to in clause (a) above, a statement of all contingent liabilities of
Guarantor and its subsidiaries which are not reflected in such financial
statements or referred to in the notes thereto (including, without limitation,
all guarantees, endorsements and other contingent obligations in respect of
indebtedness of others, and obligations to reimburse the issuer in respect of
any letters of credit), all in reasonable detail and certified by the principal
financial or accounting officer of Guarantor;

            (d) contemporaneously with the filing or mailing thereof, copies of
all material of a financial nature filed with the SEC or sent to the
stockholders of Guarantor;

            (e) promptly after they are filed with the Internal Revenue Service,
copies of all annual federal income tax returns and amendments thereto of
Guarantor;

            (f) promptly upon becoming aware thereof, written notice from
Guarantor of any event or condition which might have a material adverse effect
on the business, operations, assets, condition (financial or otherwise) of
Guarantor or any of its subsidiaries or the ability of Guarantor to perform
under this Guaranty (including but not limited to, litigation commenced against
Guarantor or any of its subsidiaries, judgments rendered against Guarantor or
any of its subsidiaries, liens filed against any property of Guarantor or any of
its subsidiaries, defaults claimed under indebtedness for borrowed money for
which Guarantor or any of its subsidiaries is primarily or secondarily liable,
or bankruptcy, insolvency or trustee or receivership proceedings commenced
against Guarantor or any of its subsidiaries), such notice to specify the nature
and the period of existence of such event or condition, the anticipated effect
thereof, and what action Guarantor is taking or proposes to take with respect
thereto; and

            (g) with reasonable promptness, such other information respecting
the business, operations, assets, liabilities and financial condition of
Guarantor and its subsidiaries as Lender may from time to time reasonably
request.

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Upon two (2) Business Days' prior notice, Guarantor will permit any officer
designated by Lender, at Guarantor's expense, to visit and inspect any of the
properties of Guarantor or any of its subsidiaries, to examine the records and
books of account of Guarantor and its subsidiaries (and to make copies thereof
and extracts therefrom) and to discuss the affairs, finances and accounts of
Guarantor and its subsidiaries with, and to be advised as to the same by, its
officers, all at such reasonable times and intervals Lender may reasonably
request.

         11. Covenants of Guarantor. Guarantor hereby covenants and agrees with
Lender that until all indebtedness guaranteed hereby has been completely repaid
and all obligations and undertakings of Borrower under, by reason of, or
pursuant to the Note and the Loan Documents have been completely performed:

            (a) Guarantor will, and will cause each of its subsidiaries to, do
or cause to be done all things necessary to preserve and keep in full force and
effect its corporate or legal existence, rights and franchises, to effect and
maintain its foreign qualifications, licensing, domestication or authorization,
except where a failure to be so qualified, licensed, domesticated or authorized
in such foreign jurisdictions would not have a materially adverse effect on its
business, assets or financial condition, and to comply with all applicable laws
and regulations (including, without limitation, environmental laws);

            (b) Guarantor will, and will cause each of its subsidiaries to,
continue to engage primarily in the business now conducted by it and them;

            (c) Guarantor will, and will cause each of its subsidiaries to, duly
pay and discharge, before the same shall become in arrears, all taxes,
assessments and other governmental charges imposed upon it and its properties,
sales or activities, or upon the income or profits therefrom, as well as claims
for labor, material, or supplies which if unpaid might become a lien or charge
on any of its property; provided that any such tax, assessment, charge or claim
need not be paid if the validity or amount thereof shall currently be contested
in good faith by appropriate proceedings and if Guarantor or such subsidiary
shall have set aside on its books adequate reserves with respect thereto; and
provided further that Guarantor or such subsidiary shall pay all such taxes,
assessments, charges and claims forthwith upon the commencement of proceedings
to foreclose any lien that may have attached as security therefor;

            (d) Guarantor will, and will cause each of its subsidiaries to,
maintain and keep the properties used or deemed by it to be useful in its
business in first-class repair, working order and condition, and make or cause
to be made all necessary and proper repairs thereto and replacements thereof;

            (e) Guarantor will, and will cause each of its subsidiaries to,
maintain with financially sound and reputable insurers, insurance with respect
to its properties and business against such casualties and contingencies and in
such types and amounts as shall be in accordance with sound business Ipractices
for companies in similar business similarly situated;

<PAGE>   10

            (f) Guarantor will keep, and will cause each of its subsidiaries to
keep, complete, proper and accurate records and books of account in which full,
true and correct entries will be made in accordance with generally accepted
accounting principles consistent with the preparation of the financial
statements heretofore delivered to Lender and will maintain adequate accounts
and reserves for all taxes (including income taxes), all depreciation,
depletion, and amortization of its properties and the properties of its
subsidiaries, all other contingencies, and all other proper reserves;

            (g) Guarantor will not, and will not permit any of its subsidiaries
to, become a party to any merger, consolidation or other business combination,
or agree to effect any asset acquisition other than the acquisition of assets in
the ordinary course of business consistent with past practices, stock
acquisition or other acquisition, except (A) the merger or consolidation of one
or more of the subsidiaries of Guarantor with and into Guarantor, or (B) the
merger or consolidation of two or more subsidiaries of Guarantor, or (C) the
merger of Guarantor with another entity provided that Guarantor is the surviving
entity;

            (h) Guarantor will not, and will not permit any of its subsidiaries
to, become a party to or agree to or affect any disposition of assets, other
than the disposition of assets in the ordinary course of business consistent
with past practice;

            (i) Guarantor will not make or permit to be made, by voluntary or
involuntary means, any transfer or encumbrance of its interest in ERT
Development Corporation, or any dilution of its interest in ERT Development
Corporation; provided, however, Guarantor may assign up to fifty percent (50%)
of the issued and outstanding shares of preferred stock in ERT Development
Corporation owned by Guarantor to the officers of Guarantor;

            (j) Guarantor shall at all times comply with all requirements of
applicable laws and regulations necessary to maintain its status as a real
estate investment trust as defined in ss.856(a) of the Code and in compliance
with the terms and conditions of this Guaranty and the other Loan Documents;

            (k) Guarantor shall at all times observe, perform and comply with
each and every term, covenant or agreement set forth in the Credit Agreement
within any applicable period of grace or notice and cure, and, in the event that
any Credit Agreement shall be terminated or no longer in full force and effect,
Guarantor shall continue to observe, perform and comply with the terms,
covenants and agreements therein, as if the same were fully set forth in this
Guaranty and a part hereof, as the same existed immediately prior to such
termination and as if the same continued in full force and effect; and

            (l) Guarantor will cooperate with Lender and execute such further
instruments and documents as Lender shall reasonably request to carry out to
their satisfaction the transactions contemplated by this Guaranty and the other
Loan Documents.

         12. Security and Rights of Set-off. Guarantor hereby grants to Lender,
as security for
<PAGE>   11
the full and prompt payment and performance of Guarantor's obligations
hereunder, a continuing lien on and security interest in any and all securities
or other property belonging to Guarantor now or hereafter held by Lender and in
any and all deposits (general or specific, time or demand, provisional or final,
regardless of currency, maturity, or the branch of Lender where the deposits are
held) now or hereafter held by Lender and other sums credited by or due from
Lender to Guarantor or subject to withdrawal by Guarantor; and regardless of the
adequacy of any collateral or other means of obtaining repayment of such
obligations, during the continuance of any Event of Default under the Note or
the Loan Documents, Lender may at any time and without notice to Guarantor
set-off and apply the whole or any portion or portions of any or all such
deposits and other sums against amounts payable under this Guaranty, whether or
not any other person or persons could also withdraw money therefrom. Any
security now or hereafter held by or for Guarantor and provided by Borrower, or
by anyone on Borrower's behalf, in respect of liabilities of Guarantor hereunder
shall be held in trust for Lender as security for the liabilities of Guarantor
hereunder.

         13. Changes in Writing; No Revocation. This Guaranty may not be changed
orally, and no obligation of Guarantor can be released or waived by Lender
except by a writing signed by a duly authorized officer of Lender. This Guaranty
shall be irrevocable by Guarantor until all indebtedness guaranteed hereby has
been completely repaid and all obligations and undertakings of Borrower under,
by reason of, or pursuant to the Note and the Loan Documents have been
completely performed.

         14. Notices. All notices, demands or requests provided for or permitted
to be given pursuant to this Guaranty (hereinafter in this paragraph referred to
as "Notice") must be in writing and shall be deemed to have been properly given
or served by personal delivery or by sending same by overnight courier or by
depositing the same in the United States mail, postpaid and registered or
certified, return receipt requested, at the addresses set forth below. Each
Notice shall be effective upon being delivered personally or upon being sent by
overnight courier or upon being deposited in the United States Mail as
aforesaid. The time period in which a response to any such Notice must be given
or any action taken with respect thereto, however, shall commence to run from
the date of receipt if personally delivered or sent by overnight courier or, if
so deposited in the United States Mail, the earlier of three (3) Business Days
following such deposit and the date of receipt as disclosed on the return
receipt. Rejection or other refusal to accept or the inability to deliver
because of changed address of which no Notice was given shall be deemed to be
receipt of the Notice sent. By giving at least thirty (30) days prior Notice
thereof, Guarantor or Lender shall have the right from time to time and at any
time during the term of this Guaranty to change their respective addresses and
each shall have the right to specify as its address any other address within the
United States of America. For the purposes of this Guaranty:

         The address of Lender is:

                  Fleet National Bank
                  100 Federal Street

<PAGE>   12
                  Boston, Massachusetts 02110
                  Attention:  Real Estate Division

         with a copy to:

                  Fleet National Bank
                  115 Perimeter Center Place, N.E.
                  Suite 500
                  Atlanta, Georgia 30346
                  Attention: Dan Stegemoeller

and a copy to each other Bank which may now or hereafter become a party to the
Loan Agreement at such address as may be designated by such Bank.

         The address of Guarantor is:

                  New Plan Excel Realty Trust, Inc.
                  1120 Avenue of the Americas
                  New York, New York 10036
                  Attention: Dean Bernstein

         15. GOVERNING LAW. GUARANTOR AND LENDER ACKNOWLEDGE AND AGREE THAT THIS
GUARANTY AND THE OBLIGATIONS OF GUARANTOR HEREUNDER SHALL BE GOVERNED BY AND
INTERPRETED AND DETERMINED IN ACCORDANCE WITH THE LAWS OF THE OF MASSACHUSETTS
(EXCLUDING THE LAWS APPLICABLE TO CONFLICTS OR CHOICE OF LAW).

         If, notwithstanding the provisions of Section 15 above, this Guaranty
is deemed to be governed by California law, then the following shall apply but
shall not in any way limit the generality of any other provisions contained in
this Guaranty.

         Guarantor hereby waives (a) any defense of Guarantor based upon
Lender's election of any remedy against Guarantor or Borrower or both; (b) any
defense based upon Lender's failure to disclose to Guarantor any information
concerning Borrower's financial condition or any other circumstances bearing on
Borrower's ability to pay all sums payable under the Loan Documents; (c) any
defense based upon any statute or rule of law which provides that the obligation
of a surety must be neither larger in amount nor in any other respects more
burdensome than that of a principal; (d) any defense based upon Lender's
election, in any proceeding instituted under the Federal Bankruptcy Code, of the
application of Section 1111(b)(2) of the Federal Bankruptcy Code or any
successor statute; (e) any right of subrogation, any right to enforce any remedy
which Lender may have against Borrower and any right to participate in, or
benefit from, any security for any of the Loan Documents now or hereafter held
by Lender; and (f) benefit of any statute of limitations affecting the liability
of the Guarantor hereunder or the enforcement hereof. Without limiting the
generality of the foregoing or any other provision hereof, Guarantor
<PAGE>   13
expressly waives any and all benefits which might otherwise be available to
Guarantor under Sections 2787 to 2855, inclusive, of the California Civil Code,
including without limitation, Sections 2809, 2810, 2819, 2839, 2845, 2849 and
2850, and all benefits which might otherwise be available to Guarantor under
Sections 2899 and 3433 of the California Civil Code and the California Code of
Civil Procedure Sections 580a, 580b, 580d and 726, or any of such sections.
Furthermore, without limitation of any waiver otherwise set forth herein,
Guarantor waives all rights and defenses arising out of an election of remedies
by the Lender even though that election of remedies, such as a nonjudicial
foreclosure with respect to the security for a guaranteed obligation, has
destroyed Guarantor's rights of subrogation and reimbursement against the
principal by operation of Section 580d of the California Code of Civil Procedure
or otherwise.

         In addition, Guarantor waives all rights and defenses that Guarantor
may have because the Borrower's debt is secured by real property. This means,
among other things:

         (A) Lender may collect from Guarantor without first foreclosing on any
real or personal property collateral pledged by Borrower; and

         (B) If Lender forecloses on any real property collateral pledged by
Borrower:

             (i) The amount of the debt may be reduced only by the price for
which that collateral is sold at the foreclosure sale, even if the collateral is
worth more than the sale price;

             (ii) Lender may collect from Guarantor even if Lender, by
foreclosing on the real property collateral, has destroyed any right Guarantor
may have to collect from Borrower.

         This is an unconditional and irrevocable waiver of any rights and
defenses Guarantor may have because Borrower's debt is secured by real property.
These rights and defenses include, but are not limited to, any rights or
defenses based upon Section 580a, 580b, 580d or 726 of the California Code of
Civil Procedure.

         16. CONSENT TO JURISDICTION; WAIVERS. GUARANTOR HEREBY IRREVOCABLY AND
UNCONDITIONALLY (A) SUBMITS TO PERSONAL JURISDICTION IN THE STATE OF
MASSACHUSETTS OVER ANY SUIT, ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO
THIS GUARANTY, AND (B) WAIVES ANY AND ALL PERSONAL RIGHTS UNDER THE LAWS OF ANY
STATE (I) TO THE RIGHT, IF ANY, TO TRIAL BY JURY, (II) TO OBJECT TO JURISDICTION
WITHIN THE STATE OF MASSACHUSETTS OR VENUE IN ANY PARTICULAR FORUM WITHIN THE
STATE OF MASSACHUSETTS, AND (III) TO THE RIGHT, IF ANY, TO CLAIM OR RECOVER ANY
SPECIAL, EXEMPLARY, PUNITIVE OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES OTHER THAN
ACTUAL DAMAGES. EACH LENDER IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY AND ALL
RIGHTS UNDER THE LAWS OF ANY STATE TO THE RIGHT, IF ANY, TO TRIAL BY JURY.
GUARANTOR AGREES THAT, IN ADDITION TO ANY METHODS OF SERVICE OF PROCESS PROVIDED
FOR UNDER APPLICABLE LAW, ALL SERVICE OF PROCESS IN ANY SUCH SUIT, ACTION OR
PROCEEDING MAY BE MADE BY CERTIFIED OR
<PAGE>   14
REGISTERED MAIL, RETURN RECEIPT REQUESTED, DIRECTED TO GUARANTOR AT THE ADDRESS
SET FORTH IN PARAGRAPH 14 ABOVE, AND SERVICE SO MADE SHALL BE COMPLETE FIVE (5)
DAYS AFTER THE SAME SHALL BE SO MAILED. NOTHING CONTAINED HEREIN, HOWEVER, SHALL
PREVENT LENDER FROM BRINGING ANY SUIT, ACTION OR PROCEEDING OR EXERCISING ANY
RIGHTS AGAINST ANY SECURITY AND AGAINST GUARANTOR PERSONALLY, AND AGAINST ANY
PROPERTY OF GUARANTOR, WITHIN ANY OTHER STATE. INITIATING SUCH SUIT, ACTION OR
PROCEEDING OR TAKING SUCH ACTION IN ANY STATE SHALL IN NO EVENT CONSTITUTE A
WAIVER OF THE AGREEMENT CONTAINED HEREIN THAT THE LAWS OF THE COMMONWEALTH OF
MASSACHUSETTS SHALL GOVERN THE RIGHTS AND OBLIGATIONS OF GUARANTOR AND LENDER
HEREUNDER OR OF THE SUBMISSION HEREIN MADE BY GUARANTOR TO PERSONAL JURISDICTION
WITHIN THE STATE OF MASSACHUSETTS. GUARANTOR HEREBY WAIVES ANY OBJECTION THAT IT
MAY NOW OR HEREAFTER HAVE TO THE VENUE OF ANY SUCH SUIT OR ANY SUCH COURT OR
THAT SUCH SUIT IS BROUGHT IN AN INCONVENIENT COURT. GUARANTOR CERTIFIES THAT NO
REPRESENTATIVE, AGENT OR ATTORNEY OF ANY LENDER HAS REPRESENTED, EXPRESSLY OR
OTHERWISE, THAT SUCH LENDER WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO
ENFORCE THEIR FOREGOING WAIVERS AND ACKNOWLEDGES THAT LENDER HAS BEEN INDUCED TO
ENTER INTO THIS GUARANTY AND THE OTHER LOAN DOCUMENTS TO WHICH THEY ARE PARTIES
BY, AMONG OTHER THINGS, THE WAIVERS AND CERTIFICATIONS CONTAINED IN THIS
PARAGRAPH 16.

         17. Successors and Assigns. The provisions of this Guaranty shall be
binding upon Guarantor and its heirs, successors, successors in title, legal
representatives, and assigns, and shall inure to the benefit of Lender, its
successors, successors in title, legal representatives and assigns.
Notwithstanding the foregoing, Guarantor may not assign any right or delegate
any duty or obligation it may have under this Guaranty.

         18. Assignment by Lender. This Guaranty is assignable by Lender in
whole or in part in conjunction with any assignment of the Note or portions
thereof, and any assignment hereof or any transfer or assignment of the Note or
portions thereof by Lender shall operate to vest in any such assignee the rights
and powers, in whole or in part, as appropriate, herein conferred upon and
granted to Lender.

         19. Severability. If any term or provision of this Guaranty shall be
determined to be illegal or unenforceable, all other terms and provisions hereof
shall nevertheless remain effective and shall be enforced to the fullest extent
permitted by law.

         20. Disclosure. Guarantor agrees that in addition to disclosures made
in accordance with standard banking practices, any Lender may disclose
information obtained by such Lender pursuant to this Guaranty to assignees or
participants and potential assignees or participants hereunder.

<PAGE>   15

         21. NO UNWRITTEN AGREEMENTS. THIS GUARANTY REPRESENTS THE FINAL
AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

         22. Time of the Essence. Time is of the essence with respect to each
and every covenant, agreement and obligation of Guarantor under this Guaranty.

         23. Consent of Guarantor. By execution of this Guaranty, Guarantor
hereby expressly consents to the amendments and restatement of the Loan
Agreement, and any amendments of the Security Documents executed
contemporaneously herewith, and acknowledges, represents and agrees that this
Guaranty remains in full force and effect and constitute the valid and legally
binding obligation of Guarantor enforceable against Guarantor in accordance with
its terms, and that the Guaranty extends to and applies to the foregoing
documents as modified and amended.

         IN WITNESS WHEREOF, Guarantor has executed this Guaranty as of the 5th
day of April, 2000.

                                  NEW PLAN EXCEL REALTY TRUST, INC., a
                                  Maryland corporation, formerly known as Excel
                                  Realty Trust, Inc.

                                  By: /s/ Dean Bernstein
                                      -----------------------------------------
                                      Name: Dean Bernstein
                                      Title: SVP

                                                [CORPORATE SEAL]
<PAGE>   16

         Lender joins in the execution of this Guaranty for the sole and limited
purpose of evidencing its agreement to waiver of the right to trial by jury
contained in Section 16(b)(i) hereof and Section 25 of the Loan Agreement.

                                  FLEET NATIONAL BANK,
                                  as Agent

                                  By: /s/ Daniel P. Stegemoeller
                                      -----------------------------------------
                                      Name: Daniel P. Stegemoeller
                                      Title: Vice President<PAGE>   1
                                                                EXHIBIT 10.60.1

                                                               [CONFORMED COPY]

                       AMENDMENT NO. 1 TO CREDIT AGREEMENT

         AMENDMENT dated as of December 31, 1999 to the Credit Agreement dated
as of September 8, 1999 (the "CREDIT AGREEMENT") among WILLIAMS COMMUNICATIONS,
INC. (the "BORROWER"), WILLIAMS COMMUNICATIONS GROUP, INC., as Guarantor, the
LENDERS party thereto (the "LENDERS") and BANK OF AMERICA, N.A., as
Administrative Agent (the "ADMINISTRATIVE AGENT"), THE CHASE MANHATTAN BANK, as
Syndication Agent, and BANK OF MONTREAL and THE BANK OF NEW YORK, as
Co-Documentation Agents.

                                  WITNESSETH:

         WHEREAS, the parties hereto have entered into the Credit Agreement and
now desire to make certain amendments to the Credit Agreement as set forth
herein;

         NOW, THEREFORE, the parties hereto agree as follows:

         SECTION 1. Defined Terms; References. Unless otherwise specifically
defined herein, each term used herein which is defined in the Credit Agreement
has the meaning assigned to such term in the Credit Agreement. Each reference to
"hereof", "hereunder", "herein" and "hereby" and each other similar reference
and each reference to "this Agreement" and each other similar reference
contained in the Credit Agreement shall, after this Amendment becomes effective,
refer to the Credit Agreement as amended hereby.

         SECTION 2. Additional Definitions. (a) Section 1.01(a) of the Credit
Agreement is hereby amended by inserting the following new defined term in
appropriate alphabetical order:

                  "Qualifying Borrower Indebtedness" means, unsecured
         Indebtedness of the Borrower to Holdings that (i) does not require the
         payment of any principal or cash interest prior to the first
         anniversary of the Term Maturity Date, (ii) is not redeemable by, or
         convertible or exchangeable for securities of the Borrower or any of
         its Subsidiaries that are redeemable by, the holder thereof, and not
         subject to any required sinking fund or other similar payment, prior to
         the first anniversary of the Term Maturity Date, (iii) is subordinated
         to the Obligations pursuant to subordination provisions at least as
         favorable to the holders of the Obligations as the provisions set forth
         in Exhibit J hereto and (iv) includes

<PAGE>   2

         no covenants, events of default or acceleration provisions other than a
         customary bankruptcy default and acceleration provision.

          (b) Section 1.01(a) of the Credit Agreement is hereby amended further
by inserting in the definition of "Senior Debt" the phrase "(other than
Qualifying Borrower Indebtedness permitted under Section 6.01(p))" immediately
following the word "Indebtedness" in the first line thereof.

         SECTION 3. Parent Guarantee. Section 5.16 of the Credit Agreement is
hereby amended by (i) adding, following the word "contributed" in clause (iv)
thereof, the expression "or lent" and (ii) adding, at the end of such clause
(iv) before the comma, the expression "or as Qualifying Borrower Indebtedness".

         SECTION 4. Indebtedness; Certain Equity Securities. (a) Section 6.01(a)
of the Credit Agreement is hereby amended by inserting, immediately following
clause (o) thereof, new clause (p) to read in its entirety as follows:

         "(p) Indebtedness of the Borrower consisting of Qualifying Borrower
         Indebtedness;"

         SECTION 5. Certain Payments of Indebtedness. Section 6.07(b) of the
Credit Agreement is hereby amended by (i) replacing the word "or" on the fourth
line thereof following the expression "Intercompany Note" with a comma, (ii)
adding, following the expression "Qualifying Holdings Debt" on the fifth line
thereof, the expression "or any Qualifying Borrower Indebtedness" and (iii)
inserting, on the third line of clause (i) thereof following the expression
"Specified Indebtedness", the expression "other than Qualifying Borrower
Indebtedness".

         SECTION 6. Exhibit J to Credit Agreement. The Credit Agreement is
hereby amended by adding, as Exhibit J thereto, Exhibit J hereto.

         SECTION 7. Representations of Borrower. The Borrower represents and
warrants that after giving effect to this Amendment (i) the representations and
warranties of the Borrower set forth in Article 3 of the Credit Agreement are
true and correct (except in the case of any such representation or warranty
that, by its terms expressly relates only to a specified earlier date, each of
which representations and warranties was true as of such specified earlier date)
and (ii) no Default has occurred and is continuing.

         SECTION 8. Governing Law. This Amendment shall be governed by and
construed in accordance with the laws of the State of New York.

         SECTION 9. Counterparts. This Amendment may be signed in any number of
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

                                        2

<PAGE>   3

         SECTION 10. Effectiveness. This Amendment shall become effective as of
the date hereof when the Administrative Agent shall have received from each of
the Loan Parties and the Required Lenders a counterpart hereof signed by such
party or facsimile or other written confirmation (in form satisfactory to the
Agent) that such party has signed a counterpart hereof.

                                       3
<PAGE>   4

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date first above written.

                                       WILLIAMS COMMUNICATIONS, INC.

                                       By: /s/ Howard S. Kalika
                                           -------------------------------------
                                           Title: Vice President and Treasurer

                                       WILLIAMS COMMUNICATIONS GROUP, INC.

                                       By: /s/ Howard S. Kalika
                                           -------------------------------------
                                           Title: Vice President and Treasurer

                                       BANK OF AMERICA, N.A.

                                       By: /s/ Roselyn Drake
                                           -------------------------------------
                                           Title: Managing Director

                                       THE CHASE MANHATTAN BANK

                                       By: /s/ Constance M. Coleman
                                           -------------------------------------
                                           Title: Vice President

                                       BANK OF MONTREAL

                                       By: /s/ W.T. Calder
                                           -------------------------------------
                                           Title: Managing Director

<PAGE>   5

                                       THE BANK OF NEW YORK

                                       By:
                                          --------------------------------------
                                          Title:

                                       SCOTIABANC INC.

                                       By: /s/ W.J. Brown
                                          --------------------------------------
                                          Title: Managing Director

                                       ABNAMRO BANK N.V.

                                       By: /s/ David Carrington
                                          --------------------------------------
                                          Title: Group Vice President

                                       By: /s/ Frances O'R. Logan
                                          --------------------------------------
                                          Title: Senior Vice President

                                       FLEET NATIONAL BANK

                                       By: /s/ Amy B. Peden
                                          --------------------------------------
                                          Title: Assistant Vice President

                                       CIBC INC.

                                       By: /s/ Michele E. Roller
                                          --------------------------------------
                                          Title: Executive Director
                                                 CIBC World Markets Corp.
                                                 as Agent

<PAGE>   6

                                       CREDIT SUISSE FIRST BOSTON

                                       By: /s/ Joel Glodowski
                                           -------------------------------------
                                           Title: Managing Director

                                       By: /s/ Chris Horgan
                                           -------------------------------------
                                           Title: Vice President

                                       DEUTSCHE BANK AG
                                       NEW YORK AND/OR CAYMAN ISLAND
                                       BRANCH

                                       By: /s/ Jon D. Storck
                                           -------------------------------------
                                           Title: Vice President

                                       By: /s/ Sangita Gupte
                                           -------------------------------------
                                           Title: Associate

                                       CREDIT LYONNAIS NEW YORK BRANCH

                                       By:
                                           -------------------------------------
                                           Title:

<PAGE>   7

                                       BANK AUSTRIA CREDITANSTALT
                                       CORPORATE FINANCE, INC.

                                       By:
                                          --------------------------------------
                                          Title:

                                       By:
                                          --------------------------------------
                                          Title:

                                       FIRST UNION NATIONAL BANK

                                       By:
                                          --------------------------------------
                                          Title:

                                       IBM CREDIT CORPORATION

                                       By: /s/ Thomas S. Curcio
                                          --------------------------------------
                                          Title: Manager of Credit

                                       THE INDUSTRIAL BANK OF JAPAN,
                                       LIMITED, NEW YORK BRANCH

                                       By:
                                          --------------------------------------
                                          Title:

<PAGE>   8

                                       BANK OF OKLAHOMA N.A.

                                       By: /s/ Robert D. Mattax
                                          --------------------------------------
                                          Title: Senior Vice President

                                       THE FIRST NATIONAL BANK OF
                                                CHICAGO

                                       By:
                                          --------------------------------------
                                          Title:

                                       KBC BANK, N.V.

                                       By: /s/ Jean-Pierre Diels
                                          --------------------------------------
                                          Title: First Vice President

                                       By: /s/ Patrick A. Janssens
                                          --------------------------------------
                                          Title: Vice President

                                       THE FUJI BANK, LIMITED

                                       By: /s/ Jacques Azagury
                                          --------------------------------------
                                          Title: Senior Vice President & Manager

<PAGE>   9

Acknowledged and agreed:

CNG COMPUTER NETWORKING GROUP, INC.
CRITICAL CONNECTIONS, INC.
DATA COMMUNICATIONS 2000, INC.
INTERNET ENGINEERING & CONSULTANT, INC.
WCS COMMUNICATIONS SYSTEMS,
     INC.
WCS MICROWAVE SERVICES, INC.
WCS, INC.
WILLIAMS COMMUNICATIONS OF
     VIRGINIA, INC.
WILLIAMS GLOBAL COMMUNICATIONS
     HOLDINGS, INC.
WILLIAMS INTERNATIONAL
     VENTURES COMPANY
WILLIAMS LEARNING NETWORK,
     INC.
WILLIAMS LOCAL NETWORK, INC.
WILLIAMS WIRELESS, INC.

All By: /s/ Howard S. Kalika
       ----------------------------
Title: Vice President and Treasurer

THE WILLIAMS COMPANIES, INC.

By: /s/ Gary R. Belitz
   --------------------------------
   Title: Controller

<PAGE>   10

                                                                     EXHIBIT J

         Williams Communications, Inc. (the "Borrower") and Williams
Communications Group, Inc. ("WCG") agree and each holder of this Promissory
Note, by its acceptance hereof hereby agrees, for the benefit of the holders of
the Senior Obligations that all indebtedness evidenced by this Promissory Note,
including principal, premium, if any, and interest, and all other amounts
payable to WCG or any other holder of this Promissory Note hereunder (including,
for all purposes of this Promissory Note, (i) any payment in respect of
redemption or purchase or other acquisition hereof and (ii) any interest that
accrues after the commencement of any case, proceeding or other action relating
to the bankruptcy, insolvency or reorganization of the Borrower (or would accrue
but for the operation of applicable bankruptcy or insolvency laws), whether or
not such interest is allowed or allowable as a claim in any such proceeding)
(collectively, the "Subordinated Obligations") shall, to the extent hereinafter
set forth, be subordinate and junior to the Senior Obligations.

         Unless and until all principal of, premium, if any, and interest on,
and all other obligations of the Borrower under, the Senior Obligations shall
have been paid in full and all commitments to extend the Senior Obligations
shall have terminated, neither the Borrower nor any of its subsidiaries or
affiliates shall make, and WCG shall not demand, accept or receive, or attempt
to collect or commence any legal proceedings to collect, any direct or indirect
payment (in cash or property or by setoff, exercise of contractual or statutory
rights or otherwise) of or on account of any amount payable on or with respect
to this Promissory Note (including any payment in respect of redemption or
purchase or other acquisition) or any interest herein. Unless and until all
principal of, premium, if any, and interest on, and all other obligations of the
Borrower under, the Senior Obligations shall have been paid in full and all
commitments to extend the Senior Obligations shall have terminated, WCG will not
commence or maintain any action, suit or any other legal or equitable proceeding
against the Borrower, or join with any creditor in any such proceeding, under
any insolvency, bankruptcy, receivership, liquidation, reorganization or other
similar law, unless the holders of the Senior Obligations shall also join in
bringing such proceeding; provided that the foregoing shall not prohibit WCG
from filing a proof of claim or otherwise participating in any such proceeding
not commenced by it.

         If WCG or any other holder of this Promissory Note shall at any time
receive any payment in respect of any Subordinated Obligation prohibited under
the second and third paragraphs of this Promissory Note, WCG or such holder, as
the case may be, shall hold all such payments in trust for the holders of the
Senior Obligations and shall promptly transmit such payment, in the form
received by it, together with any necessary endorsements, to the Administrative
Agent.

                                       J-1
<PAGE>   11

         Neither WCG nor any other holder of this Promissory Note shall be
subrogated to the rights of the holders of the Senior Obligations to receive
payments or distributions of assets of the Borrower until all amounts payable
with respect to the Senior Obligations shall be paid in full and all commitments
to extend the Senior Obligations shall have terminated; and, for the purposes of
such subrogation, no payments or distributions to the holders of the Senior
Obligations of any cash, property or securities to which WCG or any other holder
of this Promissory Note would be entitled except for these provisions shall, as
between the Borrower, its creditors other than the holders of the Senior
Obligations, and WCG or any other holder of this Promissory Note, be deemed to
be a payment by the Borrower to or on account of the Senior Obligations. The
subordination provisions of this Promissory Note are and are intended solely for
the purpose of defining the relative rights of WCG or any other holder of this
Promissory Note, on the one hand, and the holders of the Senior Obligations, on
the other hand.

         Subject to the payment in full of all of the Senior Obligations, WCG or
any other holder of this Promissory Note shall be subrogated (equally and
ratably with the holders of all subordinated indebtedness of the Borrower which,
by its terms, is not superior in right of payment to the this Promissory Note,
and ranks on a parity with this Promissory Note) to the rights of the holders of
the Senior Obligations to receive payments or distributions of cash, property or
securities of the Borrower applicable to the Senior Obligations until all
amounts owing on this Promissory Note shall be paid in full. For purposes of
such subrogation, no payments or distributions to WCG or any other holder of
this Promissory Note of cash, property, securities or other assets by virtue of
the subrogation herein provided which otherwise would have been made to the
holders of the Senior Obligations shall, as between the Borrower, its creditors
other than the holders of Senior Obligations and WCG or any other holder of this
Promissory Note, be deemed to be a payment to or on account of the Senior
Obligations. WCG and each other holder of this Promissory Note, by its
acceptance thereof, agrees that, in the event that all or any part of any
payment made on account of the Senior Obligations is recovered from the holders
of the Senior Obligations as a preference, fraudulent transfer or similar
payment under any bankruptcy, insolvency or similar law, any payment or
distribution received by WCG or any other holder on account of this Promissory
Note at any time after the date of the payment so recovered, whether pursuant to
the right of subrogation provided for in this Promissory Note or otherwise,
shall be deemed to have been received by WCG or any other holder of this
Promissory Note in trust as the property of the holders of the Senior
Obligations and WCG or any other holder of this Promissory Note shall forthwith
deliver the same to the Administrative Agent and any other representative on
behalf of the holders of the Senior Obligations for the equal and ratable
benefit of the holders of the Senior Obligations for application to payment of
all Senior Obligations in full.

                                      J-2

<PAGE>   12

         As used in this Promissory Note, the following terms shall have the
following meanings:

"Credit Agreement" means the Credit Agreement dated as of September 8, 1999
among Williams Communications, Inc., Williams Communication Group, Inc., the
Lenders party thereto, Bank of America, N.A., as Administrative Agent, The Chase
Manhattan Bank, as Syndication Agent, and Bank of Montreal and the Bank of New
York, as Co-Documentation Agents, as such Credit Agreement may be amended from
time to time.

"Obligations" has the meaning set forth in the Credit Agreement.

"Senior Obligations" means (i) the Obligations, (ii) any refinancing, extension
or replacement of any Obligation and (iii) any indebtedness or other obligations
incurred pursuant to any commitment refinancing, extending or replacing
commitments under the Credit Agreement or any refinancing, extension or
replacement thereof.

                                      J-3

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