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                                                                   EXHIBIT 10.21

                 FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT

        THIS FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT ("First Amendment"),
is dated as of December 23, 1997, by and between the following parties:

        LENDER/SECURED PARTY:   NTFC CAPITAL CORPORATION, a Delaware corporation
                                with offices at 220 Athens Way, Nashville, 
                                Tennessee 37228 and its assigns ("NTFC")

        LENDER/SECURED PARTY:   EXPORT DEVELOPMENT CORPORATION, a corporation
                                established by an Act of Parliament of
                                Canada with its principal place of business
                                at 151 O'Connor, Ottawa, Canada K1A 1K3 ("EDC")

        BORROWER/DEBTOR:        IXC CARRIER, INC., a Nevada corporation with its
                                principal place of business at 1122 South 
                                Capital of Texas Hwy., Austin, Texas 78746
                                ("Borrower")

        GUARANTOR:              IXC COMMUNICATIONS, INC., a Delaware corporation
                                with its principal place of business at 1122 
                                South Capital of Texas Hwy., Austin, Texas 78746
                                ("Guarantor")

This First Amendment changes only the terms referenced herein of the Loan and
Security Agreement -between the parties thereto dated as of July 18, 1997 (the
"Agreement"), and except as expressly amended hereby, the Agreement, including
the exhibits and schedules attached thereto, and all other documents executed in
connection therewith, remain in full force and effect as executed. Any terms not
otherwise defined herein shall have the meanings given them in the Agreement.

IN WITNESS WHEREOF, the parties have executed this First Amendment to Loan and
Security Agreement by their duly authorized representatives:

LENDER:                                     BORROWER:
------                                      --------
NTFC CAPITAL CORPORATION                    IXC CARRIER, INC.


By:/s/ L.W. Middleton                       By: /s/ James F. Guthrie

TITLE: Secretary                            TITLE: Executive Vice President and
                                                   Chief Financial Officer

DATE: 12/23/97                              DATE: 12/23/97

LENDER:                                     GUARANTOR:
------                                      ---------
EXPORT DEVELOPMENT CORPORATION              IXC COMMUNICATIONS, INC.


By: /s/ Bruce Dunlop         /s/ Stephen Davies      By: /s/ James F. Guthrie

TITLE: Financial Services    International           Executive Vice President
       Manager               Contracts Specialist    and Chief Financial Officer

DATE: 12/24/97                                       DATE: 12/23/97


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                 FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT


        THIS FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT ("First Amendment")
is dated as of December 23, 1997 by and between IXC CARRIER, INC., a Nevada
corporation ("Borrower"), IXC COMMUNICATIONS, INC., a Delaware corporation
("Guarantor"), NTFC CAPITAL CORPORATION, a Delaware corporation ("NTFC"), and
EXPORT DEVELOPMENT CORPORATION, a Canadian crown corporation("EDC").

                              B A C K G R O U N D:

        A. THE PARTIES HAVE ENTERED INTO A LOAN AND SECURITY AGREEMENT
("Agreement") dated as of July 18, 1997, providing for extensions of credit to
Borrower for the purposes stated therein.

        B. A portion of the right, title and interest of NTFC in, under and to
the Agreement and attendant Loan Documents was assigned to EDC pursuant to the
Assignment and Acceptance Agreement and the Intercreditor Agreement between NTFC
and EDC.

        C. NTFC and EDC remain willing to extend such credit to Borrower, and
Borrower remains willing to borrow funds thereunder, upon the terms and
conditions set forth in the Agreement as amended by this First Amendment.

        NOW, THEREFORE, in consideration of the premises and of the mutual
covenants herein contained and intending to be legally bound hereby, the parties
hereto agree as follows:


                                   T E R M S:

        The following provisions of the Agreement are hereby amended:

        1. Section 1.01 is amended by substituting the following definitions for
those in the Agreement:

        "Cash Flow": during any fiscal period of Guarantor, the sum of (i) net
income (or loss) (which may be a positive or negative number) for such period,
plus (ii) all non-cash items deducted in determining such net income (or loss),
plus (iii) any infusions of cash equity available to Guarantor for general
corporate purposes (including cash infusions for the Guarantor's Common Stock,
Convertible Preferred Stock, Exchangeable Preferred Stock, or other Preferred
Stock duly authorized and issued pursuant to the Guarantor's Certificate of
Incorporation and By-Laws) or advances of subordinated debt to the Guarantor,
minus (iv) all non-cash items added in determining net income (or loss) during
such period, less (v) any Equity Payments made pursuant to Section 8.04 hereof.

        "Note" or "Notes": collectively, one or more promissory notes issued by
Borrower to Lender or Lender's assignee, and all extensions, renewals,
modifications, replacements, amendments, restatements and refinancings thereof.

        2. Section 2.02 is amended by substituting the following new Section for
that in the Agreement:


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        2.02.  Notes and Payment Terms.

        (a)
        Promissory Notes. The Advances shall be evidenced by one or more Notes
        substantially in the form of Exhibit A hereto, with appropriate
        insertions. Each Note shall be executed by Borrower, payable to the
        order of Lender or Lender's assignee, and shall evidence the obligation
        of Borrower to repay all principal amounts advanced under or pursuant to
        this Agreement, together with interest and all other amounts due
        thereunder. Each Note shall be dated the Closing Date, have a stated
        maturity that is the Maturity Date, and bear interest at the Interest
        Rate from the First Borrowing Date until the Note or any amount
        thereunder is paid in full (whether on the Maturity Date, by
        acceleration or otherwise). All schedules attached to the Note shall be
        deemed a part thereof. Any such schedule may be amended by Lender from
        time to time to reflect changes in the amounts includable thereon, but
        the failure to attach or amend any schedule shall not diminish the
        obligation of Borrower to repay all amounts due hereunder or on any
        Note.

        (b)
        Interest Payments. Interest shall accrue on the principal amount
        outstanding on each Note for each separate Advance at the applicable
        Interest Rate for each Advance and shall be payable, in arrears, on each
        Interest Payment Date to the holder of the Note. Interest only shall be
        payable during the Interest Only Period, and thereafter all accrued
        interest shall be payable, in arrears, with the principal payments
        described below.

        (c)
        Principal Payments. On the Conversion Date, each Note shall
        automatically convert to a term certain of twenty (20) consecutive
        quarters, and principal shall be paid in twenty (20) equal consecutive
        quarterly installments, plus accrued interest to the holder of the Note,
        commencing on June 30, 1998 and on each Payment Date thereafter until
        the Maturity Date; provided, however, that the principal payment amounts
        shall be recalculated by Lender if any Advances are made hereunder after
        the Conversion Date, based on the aggregate amount of all Advances made
        at any time. The amount of each quarterly payment shall be calculated,
        at the outset, by amortizing the amount of all principal amounts
        outstanding on the Conversion Date. It is intended that the above
        amortization schedule will fully amortize the principal amounts advanced
        under all of the Notes. The final payment on a Note shall be in an
        amount equal to all outstanding principal, accrued and unpaid interest,
        premiums, and apportioned expenses, fees, penalties and all other unpaid
        charges due under that Note and this Agreement.

        (d)
        Late Payments and Default Rate. Notwithstanding the foregoing, if
        Borrower shall fail to pay within ten (10) days after the due date any
        principal amount or interest or other amount payable under this
        Agreement or under any Note, Borrower shall pay to Lender and/or to the
        holder of any Note not held by Lender, to defray the administrative
        costs of handling such late payments, an amount equal to interest on the
        amount unpaid, to the extent permitted under applicable law, at the
        Default Rate (instead of the Interest Rate), from the due date until
        such overdue principal amount, interest or other unpaid amount is paid
        in full (both before and after judgment) whether or not any notice of
        default in the payment thereof has been delivered under Section 9.01
        hereof. In addition, but without duplication, upon the occurrence and
        during the continuance of an Event of Default, all outstanding amounts
        hereunder shall bear interest at the Default Rate (instead of the
        Interest Rate) until such amounts are paid in full or such Event of
        Default is waived in writing by Lender.


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        (e)
        Excess Interest. Notwithstanding any provision of any Note, this
        Agreement or any other Loan Document to the contrary, it is the intent
        of Lender and Borrower that Lender or any holder of any Note shall never
        be entitled to receive, collect, reserve or apply, as interest, any
        amount in excess of the maximum rate of interest permitted to be charged
        by applicable Law, as amended or enacted from time to time. In the event
        Lender, or any holder of any Note, ever receives, collects, reserves or
        applies, as interest, any such excess, such amount which would be
        excessive interest shall be deemed a partial prepayment of principal and
        treated as such, or, if the principal indebtedness and all other amounts
        due are paid in full, any remaining excess funds shall immediately be
        applied to any other outstanding indebtedness of Borrower due to Lender,
        and if none is outstanding, shall be paid to Borrower. In determining
        whether or not the interest paid or payable, under any specific
        contingency, exceeds the highest lawful rate, Borrower and Lender shall,
        to the maximum extent permitted under applicable law, (a) exclude
        voluntary prepayments and the effects thereof as it may relate to any
        fees charged by Lender, and (b) amortize, prorate, allocate, and spread,
        in equal parts, the total amount of interest throughout the entire term
        of the indebtedness; provided that if the indebtedness is paid and
        performed in full prior to the end of the full contemplated term hereof,
        and if the interest received for the actual period of existence hereof
        exceeds the maximum lawful rate, Lender or any holder of any Note shall
        refund to Borrower the amount of such excess or credit the amount of
        such excess against the principal portion of the indebtedness, as of the
        date it was received, and, in such event, Lender shall not be subject to
        any penalties provided by any laws for contracting for, charging,
        reserving or receiving interest in excess of the maximum lawful rate.

        4. Schedule 2.02 attached hereto shall be attached to the Agreement in
replacement of the Schedule 2.02 attached to the Agreement at the Closing.

        5. Schedule 4.26 attached hereto shall be attached to the Agreement in
replacement of the Schedule 4.26 attached to the Agreement at the Closing.

        6. Schedule 6.02 attached hereto shall be attached to the Agreement in
replacement of the Schedule 6.02 attached to the Agreement at the Closing.

        7. The First Amendment to the Disclosure Schedule attached hereto shall
be attached to the Agreement as an amendment to the Disclosure Schedule attached
to the Agreement at the Closing.

              END OF FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT
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