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                                                                   EXHIBIT 10.21

                                    GUARANTY


                  This GUARANTY (the "Guaranty"), dated as of October 1, 1999,
made by First International Bank, a Connecticut bank and trust company, (the
"Guarantor"), in favor of First Union Securities, Inc. ("FUSI").

                  WHEREAS, FIB Funding Trust (the "Issuer"), the Guarantor,
FUSI, Variable Funding Capital Corporation, First Union National Bank and the
Liquidity Purchasers have entered into a Note Purchase Agreement, dated as of
October 1, 1999 (the "Note Purchase Agreement") pursuant to which the Purchasers
named therein will acquire interests in a note to be issued by the Issuer
pursuant to an Indenture of the Trust, dated as of October 1, 1999 (the
"Indenture") between the Issuer and HSBC Bank USA, as Indenture Trustee; and

                  WHEREAS, pursuant to the Note Purchase Agreement, the Issuer
has agreed to pay certain increased costs, expenses and taxes as contemplated in
Sections 2.4 and 2.5 of the Note Purchase Agreement;

                  WHEREAS, the execution and delivery of this Guaranty by the
Guarantor is a condition to the initial Purchase contemplated by the Note
Purchase Agreement;

                  WHEREAS, the Guarantor will derive substantial benefit from
the transactions contemplated by the Note Purchase Agreement and the Indenture;
and

                  WHEREAS, capitalized terms used herein and not otherwise
defined herein shall have the meanings ascribed to such terms in the Note
Purchase Agreement and the Indenture.

                  NOW, THEREFORE, for good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the Guarantor hereby
unconditionally agrees as follows:

                  SECTION 1.        The Guaranty.

                  (a) The Guarantor hereby unconditionally and absolutely
guarantees the full and timely payment to the applicable party of all
obligations and amounts due by the Issuer pursuant to Section 2.4 and 2.5 of the
Note Purchase Agreement.

                  (b) The obligations of the Guarantor under this Guaranty shall
not terminate upon or otherwise be reduced by an Event of Default pursuant to
the Indenture, by any amendment entered into with the written consent of the
Guarantor to the Note Purchase Agreement or the Indenture or by any breach by
any party to any such agreements of its obligations thereunder.




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                  (c) No failure on the part of FUSI to exercise, no delay in
exercising, and no course of dealing with respect to, any right or remedy
hereunder will operate as waiver thereof, nor will any single or partial
exercise or any right or remedy hereunder preclude any other further exercise
thereof or the exercise of any other rights or remedy. This Guaranty may not be
amended or modified except by written agreement of the Guarantor and FUSI and no
consent or waiver hereunder shall be valid unless in writing and signed by FUSI.

                  (d) This Guaranty is a continuing guarantee and (i) shall
apply to all amounts due under Section 2.4 and 2.5 of the Note Purchase
Agreement whenever arising, (ii) shall remain in full force and effect until
payment in full or discharge of the amounts due under Sections 2.4 and 2.5 of
the Note Purchase Agreement and/or enforcing any rights hereunder, (iii) shall
be binding upon the Guarantor and its successors and assigns and (iv) shall
inure to the benefit of, and be enforceable by, FUSI and its successors,
transferees and assigns.

                  SECTION 2.        Representations and Warranties.

                  In making this Guaranty the Guarantor represents and warrants
to FUSI that:

                  (a) Organization and Good Standing. The Guarantor is a
Connecticut chartered bank and trust company duly organized, validly existing
and in good standing under the laws of the State of Connecticut and has the
corporate power to own its assets and to transact the business in which it is
currently engaged.

                  (b) Authorization; Binding Obligations. The Guarantor has the
power and authority to make, execute, deliver and perform this Guaranty and all
of the transactions contemplated under this Guaranty, and has taken all
necessary corporate action to authorize the execution, delivery and performance
of this Guaranty. When executed and delivered, this Guaranty will constitute the
legal, valid and binding obligation of the Guarantor enforceable in accordance
with its terms, except as enforcement of such terms may be limited by
bankruptcy, insolvency or other similar laws relating to or affecting the
enforcement of creditors' rights generally and by the availability of equitable
remedies.

                  (c) No Consent Required. The Guarantor is not required to
obtain the consent of any other party or any consent, license, approval or
authorization from, or registration or declaration with, any governmental
authority, bureau or agency in connection with the execution, delivery,
performance, validity or enforceability of this Guaranty the failure of which so
to obtain would have a material adverse effect on the business, properties,
assets or condition (financial or otherwise) of the Guarantor.

                  (d) No Violations. The execution, delivery and performance of
this Guaranty by the Guarantor will not violate any provision of any existing
law or regulation or any order or decree of any court or the Certificate of
Incorporation or Amended and Restated Bylaws of the Guarantor, or constitute a
material breach of any mortgage, indenture, contract or other material agreement
to which the Guarantor is a party or by which the Guarantor may be bound.


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                  (e) Litigation. No litigation or administrative proceeding of
or before any court, tribunal or governmental body is currently pending, or to
the knowledge of the Guarantor threatened, against the Guarantor or any of its
properties or with respect to this Guaranty which, if adversely determined,
would in the opinion of the Guarantor have a material adverse effect on the
transactions contemplated by this Guaranty.

                  SECTION 3.        Miscellaneous.

                  THIS GUARANTY SHALL BE CONSTRUED IN ACCORDANCE WITH AND
GOVERNED BY THE INTERNAL LAWS OF THE STATE OF NEW YORK APPLICABLE TO CONTRACTS
MADE AND TO BE PERFORMED THEREIN WITHOUT REGARD TO CONFLICTS OF LAW PRINCIPLES.


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                  IN WITNESS WHEREOF, First International Bank has duly executed
this Guaranty as of the day and year first written above.


                                                     FIRST INTERNATIONAL BANK



                                                     By: /s/ Leslie Galbraith
                                                         ---------------------
                                                     Name:   Leslie Galbraith
                                                     Title:  President


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