EXHIBIT 2.5.1.3

                AGREEMENT BETWEEN WORLDCOM NETWORK SERVICES INC.
                          AND ABLE TELCOM HOLDING CORP.
                                JANUARY 26, 1999

         This Agreement ("Agreement") is the definitive agreement referred to in
paragraph 7 of an agreement between the parties dated September 9, 1998 (the
"September Agreement") and supersedes the September Agreement. The parties
agrees as follows:

         1. NOTE TERMS. The existing Promissory Note with Able Telcom Holding
Corp. ("Able") as the maker and MFS Communications Company, Inc. ("MFS") as the
payee shall be assigned to WorldCom Network Services, Inc. ("WorldCom") and
shall be replaced by a promissory note of Able payable to WorldCom in the
principal amount of $30,000,000 bearing interest at 11.5% from September 1,
1998.

         The Maturity Date of the Note will be December 15, 2000 (the "Maturity
Date"). Interest shall accrue and be payable on February 28, 1999 and quarterly
thereafter and on the Maturity Date.

         The Note may be prepaid in part or in total without penalty.

         The principal amount of the Note shall be prepaid as follows:

         a.       Subject to the consent of NationsBank, N.A., after the date
                  hereof, by applying as a credit thereto an amount equal to 8%
                  of the amount otherwise payable by WorldCom, or any affiliate
                  thereof, to Able, or any affiliate thereof, under any
                  "Management Services Agreement" ("MSA"), including, without
                  limitation, the MSA dated July 2, 1998;

         b.       By Able paying WorldCom on the first business day after Able
                  receives the proceeds of any of the following:

                  i.       $7,000,000 upon the sale of NYSTA conduit;

                  ii.      $1,500,000 upon payment by The Williams Companies of
                           a fee for the installation of conduit; and

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                  iii.     The greater of 50% of the net profits or 25% of the
                           proceeds received from time to time under any
                           maintenance agreement associated with the sale of
                           NYSTA conduit.

         2. ADDITIONAL PAYMENTS. On December 29, 2000, Able shall pay to
WorldCom the following amounts, if positive:

                  a.       The difference between $12,000,000 related to losses
                           on MFS Network Technologies, Inc. ("MFSNT") projects
                           in existence on March 31, 1998 and recorded by MFSNT
                           as of June 30, 1998 and the amount of the actual
                           losses recorded as of the Maturity Date; and

                  b.       The difference between $5,000,000 recorded as
                           reserves for the litigation described on SCHEDULE 1
                           attached hereto (the "Litigation") and the aggregate
                           costs of Able in defending the Litigation, and
                           payments made in settlement or in payment of
                           judgments with respect to the Litigation, as of the
                           Maturity Date.

         3. OTHER DOCUMENTS. The Stock Pledge Agreement and the stock options
dated July 2, 1998, shall remain outstanding and in full force and effect,
except that the exercise and registration periods of each shall be extended one
year and except that the lien is subordinated to NationsBank, N.A.

         4. EQUITY AWARD. The Equity Award referred to in paragraph 4 of the
September Agreement has been effected by the execution and delivery of Stock
Appreciation Rights Agreements dated on or about January 8, 1999.

         5. INDEMNIFICATION. Able will indemnify and hold harmless WorldCom, and
its affiliates, and each of their respective employees, representatives,
officers and directors (the "Indemnified Parties") from and against any and all
claims, liabilities, losses, damages, actions, attorneys' fees and demands (the
"Indemnified Losses") resulting from the claims, demands, investigations,
proceedings or lawsuits of or by any person arising out of the business
operations acquired in the MFSNT acquisition EXCEPT for Michigan township for
access rights and the Sirit litigation.

         Able shall pay for or reimburse an Indemnified Party for any
ascertained Indemnified Loss in advance of a final disposition of the matter as
to which indemnification is sought within ten (10) days after submission of a
claim for Indemnified Losses by an Indemnified Party.

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         6. PERFORMANCE BONDS. Promptly after the closing of the transactions
contemplated by this Agreement, Able shall cause WorldCom to be released from
any and all liability on existing performance bonds and reimbursement agreements
(other than bond E-470 Project) relating to any project to which MFSNT is or was
a party.

         7. MUTUAL RELEASES The parties shall enter into mutual releases in
customary form with respect to matters arising before the date hereof, but
excluding obligations hereunder and other outstanding documentation between
WorldCom, Able and their affiliates.

         8. LEGAL INTENT. The Parties intend to be legally bound by this
Agreement and agree that this Agreement contains the necessary material items to
be considered a contract.

         9. REMEDIES. The parties agree that in addition to all other remedies
which an aggrieved party may have, this Agreement may be enforced by either
party by an action for specific performance in any court of competent
jurisdiction.

         This Agreement is entered into this 26th day of January, 1999.

WORLDCOM NETWORK                           ABLE TELCOM HOLDING CORP.
SERVICES INC.

By: /s/ DAVID E. MEYERS                    By: /s/ BILLY V. RAY
    --------------------------                 ------------------------------
Name: DAVID E. MEYERS                      Name: BILLY V. RAY
      ------------------------                   ----------------------------
Title: V.P. and Controller                 Title: CEO and President
       -----------------------                    ---------------------------


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