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                                                                   Exhibit 10.18

                                    GUARANTY


         This GUARANTY (the "Guaranty"), dated as of December 1, 1999, made by
First International Bancorp, Inc., a Delaware corporation, (the "Guarantor"), in
favor of Prudential Securities Credit Corporation ("Lender").

         WHEREAS, the Lender and FIB Holdings, Inc. ("Holdings") have entered
into a Revolving Commercial Loan Warehouse and Security Agreement, dated as of
December 1, 1999 (the "Warehouse Agreement") pursuant to which the Lender
intends to lend and Holdings intends to borrow up to a maximum of $75,000,000 to
fund the holding of Commercial Loans; and

         WHEREAS, pursuant to the Warehouse Agreement, Holdings has agreed to
reimburse and indemnify the Lender as contemplated in Section 12 of the
Warehouse Agreement;

         WHEREAS, the execution and delivery of this Guaranty by the Guarantor
is a condition to the Loan contemplated by the Warehouse Agreement;

         WHEREAS, the Guarantor will derive substantial benefit from the
transactions contemplated by the Warehouse Agreement; and

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

         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 Holdings pursuant to Section 12 of the Warehouse Agreement;
provided, however, that the Guarantor shall not guarantee (i) the repayment of
the Secured Note or any Pledged Commercial Loan or the value or collectibility
of any Collateral therefor (or any indemnification obligation in respect
thereof), or (ii) any loss or expense incurred by the Lender as a result of any
non-payment of the Secured Note or any Pledged Commercial Loan or any action
taken to seek to collect the Secured Note or any Pledged Commercial Loan (or any
indemnification obligation in respect thereof).

         (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
Warehouse Agreement, by any amendment entered into with or without the written
consent of the Guarantor to the
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Warehouse Agreement or by any breach by any party to any such agreements of its
obligations thereunder.

         (c)      No failure on the part of the Lender 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 the Lender
and no consent or waiver hereunder shall be valid unless in writing and signed
by the Lender.

         (d)      This Guaranty is a continuing guarantee and (i) shall apply to
all amounts guaranteed under Section 1(a) above, whenever arising, (ii) shall
remain in full force and effect until payment in full or discharge of the
amounts due under Sections 12 of the Warehouse 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, the
Lender and its successors, transferees and assigns.

         SECTION 2. Representations and Warranties.

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

         (a)      Organization and Good Standing. The Guarantor is a Delaware
corporation duly organized, validly existing and in good standing under the laws
of the State of Delaware 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


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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.

         (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 Bancorp, Inc. has duly executed
this Guaranty as of the day and year first written above.


                                             FIRST INTERNATIONAL BANCORP, INC.



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


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