EXHIBIT 10.43


                                                               February 23, 2000
Alan Levy
12 Old Farms Road
Woodcliff Lake, New Jersey 07675

Dear Mr. Levy:

          The  purpose  of  this  letter  is to set  forth  the  agreement  (the
"Agreement")  between you and Viatel, Inc. and its subsidiaries and predecessors
(hereinafter  referred to collectively as "Viatel")  regarding your  resignation
from Viatel as an employee and director.

          1.   RESIGNATION/TRANSITION   SERVICES.   (a)  Viatel   accepts   your
resignation  as an officer and  director of Viatel  effective  February 23, 2000
(the  "Effective  Date").  From the date hereof through and including  March 31,
2000 (the "Termination  Date"), you shall continue to provide services to Viatel
as a non-executive  employee, for a maximum of twenty (20) hours per week, which
will be performed in a maximum of three (3) business days per week. In the event
that you perform  services in excess of twenty (20) hours in any week, your time
commitment  for any  subsequent  week will be  reduced by the amount of any such
excess hours. From the date hereof through the Termination Date (the "Transition
Period"),  you will  report  solely to William  Murphy and will  assist him with
regard to transitional issues. Viatel acknowledges and agrees that the principal
location for the  performance  of such  transitional  services will be either at
your principal residence in Woodcliff Lake, New Jersey or at Viatel's offices in
Now York,  except that, upon reasonable  notice,  Viatel may reasonably  request
that you perform such act-Vices in the United Kingdom or in any other country in
which Viatel  conducts its  business.  In the event you are requested to perform
services  outside  the United  States,  Viatel  will  assist you with  regard to
planning  your  travel  arrangements  and will pay for  your  business  expenses
associated  with any such  business  trip (which  shall  include  business-class
airfare).  Notwithstanding anything herein to the contrary,  Viatel acknowledges
that  you  will be  taking  a  one-week  vacation  paid by  Viatel  for the week
commencing  March 25,  2000 and that you will not be  required  to  perform  any
service during that week, however, you agree to be reasonably available by phone
to respond to any issues that may arise.

          (b) Through the  Termination  Date,  Viatel will reimburse you for all
unpaid business  expenses  incurred or paid by you prior to the Termination Date
in connection  with the  performance  of your duties prior to the date hereof or
contemplated   hereby,   upon  presentation  of  appropriate   documentation  in
accordance  with Viatel's  customary  procedures and policies  applicable to its
executives, Without limiting the generality of the foregoing Viatel acknowledges
that it is  responsible  fur, and shall  promptly pay, all  reasonable  business
expenses billed to your corporate American Express card.

          (c) You will have no authority to bind, make any commitments on behalf
of or, except as specifically contemplated hereunder, otherwise act an behalf of
Viatel in any manner  whatsoever  on or after the date hereof.  You agree not to
take any action, or intentionally fail to take any action, which would cause any
third party to assume that you have any such authority.


<PAGE>

          2. PAYMENT AND  BENEFITS.  Viatel will provide you with the  following
payments and benefits:

          (a) SALARY. On the Effective Date, Viatel will pay you a cash lump sum
payment equal to the amount, if any, of accrued but unpaid base salary.

          (b) TRANSITION  PAYMENTS.  During the Transition  Period,  Viatel will
continue to pay you your base salary,  based on the rate of your current  annual
base salary of $345,000,  payable in accordance with Viatel's payroll  practices
applicable to you in effect prior to the date hereof.

          (c) BONUS. In the event that Viatel pays bonuses to its current senior
executives with employment  agreements with respect to services performed in the
2000  calendar  year,  upon the earlier of (i) the date that bonuses are paid to
such Viatel  executives  with respect to the 2000  calendar year or (ii) January
31, 2001, Viatel will pay you a cash lump sum representing the pro rated portion
of your Bonus Award (as defined in your  employment  agreement with Viatel dated
August 27, 1999 (the  "Employment  Agreement"))  as if you were employed for the
entire  2000  Performance  Year (as  defined in the  Employment  Agreement)  and
multiplying  such Bonus Award by a fraction,  of which: (i) the numerator is the
number of days beginning of January 1, 2000 and ending on the  Termination  Date
and (ii) the denominator is 365. The parties hereto  acknowledge  that the Bonus
Award is intended to be calculated and made in accordance with Section 3.2(c) of
the Employment Agreement.

          (d) SEVERANCE.  Subject to Section 12 hereof, on the Termination Date,
Viatel will pay you a cash lump sum payment of $57,500,  representing  severance
equal to two (2) months' base salary. In addition to the foregoing, in the event
that JazzTel plc, any of its subsidiaries or any entity  controlled,  indirectly
or directly by, or under common  control with,  Martin  Varsavsky,  completes an
acquisition  of  Viatel  commenced  at any  time  from the  date  hereof  to and
including  August  23,  2000,  Viatel  will pay you a cash lump sum  payment  of
$500,000 (the "COC Severance Amount).

          (e) 401(K)/RETIREMENT  PLANS. You will be entitled to elect at anytime
on or after the Termination  Date, a distribution of any vested accrued benefits
under  any  401(k),  pension  or other  type of  retirement  plan  sponsored  or
maintained by Viatel or any of its subsidiaries. Without limiting the generality
of the foregoing,  on the Termination Date, Viatel will cause the trustee of the
Destia 401(k) Plan to distribute  your entire account balance under such plan by
wire  transfer  in  a  direct  rollover  to  an  individual  retirement  account
established at Donaldson, Lufkin & Jenrette ("DLJ") by you.

          (f) BENEFIT PLAN  PARTICIPATION.  Viatel will continue to maintain any
health,  disability,  AD&D, business travel and life insurance coverage to which
you were entitled immediately prior to the date hereof, and Viatel will continue
to pay the employer  portion of the applicable  premiums,  until the Termination
Date.  On and  after  the  Termination  Date,  you,  your  spouse  and  eligible
dependents may elect COBRA  continuation  health  coverage for up to an 18-month
period  or such  longer  period  as  provided  in COBRA at your  expense  at the
standard  COBRA rate  applicable  to other former  employees.  No later than the
Termination  Date  we will  provide  more  information  to you  regarding  COBRA
benefits and the election forms.  Except with respect to your, your spouse's and
your eligible  dependents' rights under COBRA,  failure of Viatel to provide any
such  information  and  forms,  however,  shall not in any  event  result in any
adverse impact on Viatel or any rights it may have under this Agreement.


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<PAGE>

          (g) NO OTHER  COMPENSATION OR BENEFITS.  Except as otherwise  provided
herein,  you  will not be  entitled  to any  compensation  or  benefits  (or any
reimbursement  therefor) or to participate in any employee  benefit  programs of
Viatel on or after the date hereof.

          (h)  TIMING  OF   PAYMENTS.   Except  with   respect  to  the  amounts
contemplated  by  Sections  2(c) and 2(d)  hereof,  each cash  lump sum  payment
provided under this  Agreement  shall be paid by Viatel on the Effective Date or
as soon as administratively  practicable thereafter,  but in no event later than
three (3) business days following the Effective  Date. Any COC Severance  Amount
shall  be paid  by  Viatel  immediately  following  any  acquisition  of  Viatel
contemplated  by Section 2(d) but in no event later than three (3) business days
after the consummation of such acquisition.  The bonus described in Section 2(c)
shall be paid by  Viatel  in  accordance  with the  terms of such  section.  The
severance (other than the COC Severance  Amount) described on Section 2(d) shall
be paid on the Termination Date.

          3.  OPTIONS AND  RESTRICTED  STOCK.  (a) You  currently  hold,  either
directly or  indirectly  through Levy  Investment  Partners,  L.P.  options (the
"Options") to purchase a total of 1,356,109 shares of Viatel common stock,  $.01
par value per share (the "Common Stock"), and 16,123 shares of restricted Common
Stock (the "Restricted Stock").

          The Options  currently  held by you,  either  directly or  indirectly,
consist of the following:

<TABLE>
<CAPTION>
               NUMBER OF COMMON STOCK
                      SUBJECT
 GRANT DATE          TO OPTIONS           EXERCISE PRICE             VESTED
 ----------          ----------           --------------             ------
 <S>                   <C>                      <C>            <C>
 10/31/96              850,667                  $ 5.41                Yes
 05/03/99              231,400                  $22.41                Yes
 05/03/99              115,700                  $33.71                Yes
 05/03/99              115,700                  $44.94                Yes
 01/01/00               42,642                  $49.313        Become vested on
                                                               Termination Date
</TABLE>

          (b) Viatel  hereby  acknowledges  and agrees that:  (i) on January 31,
2000,  you  exercised an incentive  stock  option to purchase  11,058  shares of
Common Stock  (granted on October 31, 1996);  and (ii) on January 18, 2000,  you
exercised an incentive stock option to purchase 62,909.96 shares of Common Stock
(granted on October  31,  1996),  Viatel  further  acknowledges:  (i) receipt of
payment of the aggregate  exercise price in an amount equal to $399,984.55;  and
(ii) that no withholding taxes apply to such exercise.  On the date hereof or as
soon as administratively  practicable  thereafter but in no event after five (5)
business  days from the date hereof,  Viatel shall deliver to DLJ on your behalf
73,967  shares of Common Stock and cash equal to .96 of a share of Common Stock.
The incentive stock options  described under this Section 3(b) shall be referred
to as the "Exercised ISOs."


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<PAGE>

          (c) Viatel and you hereby agree that  notwithstanding any provision to
the contrary in: (i) the Amended and Restated  Econophone,  Inc.  1996  Flexible
Incentive  Plan;  (ii) the  Incentive  Stock  Option  Agreement  between you and
Econophone, Inc., dated October 31, 1996; (iii) the Destia Communications, Inc.,
1999 Flexible  Incentive Plan; (iv) the Incentive Stock Option Agreement between
you and Destia Communications, Inc., dated May 3, 1999; (v) Viatel, Inc. Amended
Stock Incentive Plan, or (vi) the Stock Option Agreement, dated January 3, 2000,
or the Restricted Stock Agreement, dated January 4, 2000, all options and shares
of Restricted  Stock not  currently  vested on the date hereof shall vest on the
Termination  Date  (i.e.,  by June 30,  2000) and with  respect  to the  Options
granted on  January 4, 2000,  be  exercisable  in full on the  Termination  Date
hereof  and at any  time  within  the  thirty  (30)  day  period  following  the
Termination Date (i.e., by May 1, 2000). On the Termination  Date, the shares of
Restricted  Stock  shall no longer be  restricted  and shall be shares of Common
Stock.

          (d) In the event that you fail to exercise  any of the Options in full
by June 30, 2000 with respect to Options granted prior to January 4, 2000 and by
May 1, 2000 with  respect  to the  Options  granted  on  January  4,  2000,  all
unexercised  Options  shall  be  forfeited.  Viatel  acknowledges  that  you may
exercise  your  Options  and pay the  applicable  exercise  price by any  method
permitted by the applicable agreement. Viatel acknowledges and hereby represents
and warrants that:

        (i)      all  shares of  Common  Stock  subject  to the  Options  or the
                 Exercised  ISO  and all shares of Common Stock which relate to
                 the Restricted Stock vested hereunder are validly registered on
                 a Form S-8 (registration  statement)  previously filed with the
                 Securities and Exchange Commission;

        (ii)     on  and  after  the  date   hereof,   you  may  sell,   without
                 restriction,  any shares of Common Stock acquired upon exercise
                 of the  Options  or the  Exercised  ISOs or by the  vesting  of
                 shares of Restricted  Stock,  except with respect to the volume
                 trading  limitations  under  Rule  144 to the  extent  required
                 therein;

        (iii)    the grant of  Restricted  Stock and the  January 4, 2000 option
                 grant were made by Viatel's  Board of  Directors  or  committee
                 consisting solely of at least two (2) "non employee  directors"
                 (as  such  term is  defined  in Rule  16b-3  promulgated  under
                 Section  16(b)  of the  Securities  Exchange  Act of 1934  (the
                 "Exchange Act"));

        (iv)     you will not be required to make any representation or warranty
                 to Viatel in  connection  with the  exercise  of any Option and
                 Viatel will not impose any  impediments or restrictions on your
                 ability to exercise any of your Options;

        (v)      you  will  not  be an  "insider"  under  Section  16(a)  of the
                 Exchange Act and,  accordingly,  you will not be subject to the
                 restrictions  under  Sections 16(a) and (b) of the Exchange Act
                 with regard to activities or  transactions  after the Effective
                 Date; and

        (vi)     Viatel  shall  deliver  to  you  the  shares  of  Common  stock
                 underlying  any Option no later than  seven (7)  business  days
                 after you exercise any such Option.


                                       4
<PAGE>

          (e) Viatel and you agree that except as  otherwise  specified  herein,
you shall have no entitlement  to any incentive  performance  awards,  including
awards or vesting of cash bonuses.

          4. YOUR  RELEASE.  (a) In  consideration  of the payments and benefits
provided to you under this Agreement,  you hereby release and discharge  Viatel,
its  affiliates  and with  respect to any actions,  omissions,  matter or events
relating to Viatel or its  affiliates,  their  respective  partners,  directors,
officers, employees and agents (collectively, "Viatel Persons") from any and all
claims,  actions,  causes of  action,  damages,  liabilities,  promises,  debts,
compensation,  losses,  obligations,  costs or  expenses  of any kind or nature,
whether  known or unknown,  which you ever had, now have or hereafter  may have,
against each or any of the Viatel Persons,  including, but not limited to, those
arising  from or related to your  employment  relationships  with  Viatel or the
termination of such  employment,  any alleged  violation of any covenant of good
faith and fair dealing  relative to your  employment or any applicable  labor or
employer-employee  statute,  regulation or ordinance,  whether federal, state or
local  (included by way of specificity  but not of limitation,  Title VII of the
Civil Rights Act of 1964, the Americans with  Disabilities Act, the Civil Rights
Act of 1991,  any  amendments  to such  acts  and any and all  state  and  local
discrimination laws).

          Notwithstanding  the foregoing,  the foregoing release shall not apply
to any payment, compensation, benefits or other rights to which you are entitled
under this Agreement.

          (b) It is also agreed that this  Agreement  shall not be admissible in
any further  proceedings  between us except in a proceeding relating to a breach
of the provisions of this Agreement.

          (c) SPECIFIC RELEASE OF ADEA CLAIMS.  In consideration of the payments
and benefits provided to you under this Agreement you hereby release and forever
discharge  Viatel,  each of its  subsidiaries  and  affiliates and each of their
respective  officers,  employees,  directors and agents from any and all claims,
actions  end  causes  of  action  that you may have as of the date you sign this
Agreement  arising under the Federal Age  Discrimination  in  Employment  Act of
1967,  as  amended,  and  the  applicable  rules  and  regulations   promulgated
thereunder  ("ADEA").  By signing this  Agreement,  you hereby  acknowledge  and
confirm the  following:  (i) you were advised by Viatel in connection  with your
termination  to consult  with an attorney of your choice  prior to signing  this
Agreement and to have such attorney  explain to you the terms of this Agreement,
including,  without  limitation,  the terms  relating to your  release of claims
arising  under  ADEA;  (ii)  you have  been  given a period  of not  fewer  than
twenty-one (21) days to consider the terms of this Agreement and to consult with
an attorney of your choosing with respect  thereto,  and (iii) you are providing
the release and  discharge  set forth in this  Section 4(c) only in exchange for
consideration  in  addition  to  anything  of  value to  which  you are  already
entitled.

          (d) You agree and  understand  that you shall not construe or treat an
aspect of the  Agreement as any  admission  of liability of any Viatel  Persons'
part.


                                       5
<PAGE>

          5. VIATEL RELEASE.  (a) The Viatel Persons jointly and severally,  all
and  singularly,  release and  discharge  you from any and all claims,  actions,
causes of action, damages, liabilities,  promises, debts, compensation,  losses,
obligations,  costs or expenses of any kind or nature, whether known or unknown,
which any of the Viatel Persons ever had, now have or hereafter may have against
you,  including,  but not  limited  to,  those  arising  from or related to your
employment  relationship with Viatel or the termination of such employment,  any
alleged violation of any covenant of good faith or fair dealing,  all common law
claims now existing or hereafter  recognized,  claims for negligence,  breach of
fiduciary duty,  interference with actual or prospective  contractual relations,
misrepresentation,  fraud, promissory,  estoppel,  equitable estoppel, breach of
contract or any other type of claim. Viatel does not waive or release any rights
set forth in this Agreement.

          (b) It is agreed  and  understood  that the Viatel  Persons  shall not
construe or treat any aspect of this  Agreement as any admission of  liabilities
on your part.

          6. COOPERATIONS. From and after the date hereof, you will cooperate in
all  reasonable  respects with Viatel and its  respective  directors,  officers,
attorneys and experts in connection with the conduct of any action,  proceeding,
investigation or litigation  involving Viatel,  solely with respect to events or
actions which occurred when you were employed by Viatel; provided, however, that
you will be entitled to: (i) reasonable  notice from Viatel of Viatel's  request
hereunder;  (ii)  full  reimbursement  by Viatel  of your  documented  costs and
expenses  incurred in connection  with your  cooperation  hereunder  (including,
without limitation, your reasonable attorneys' fees and expenses); (iii) payment
by Viatel for your actual  time spent  cooperating  with  Viatel,  as  described
herein, at any hourly rate of $300.00 per hour; and (iv) be indemnified and held
harmless by Viatel for your actions taken in accordance with this paragraph.

          7. CONFIDENTIALITY. You acknowledge that you have been provided access
to information  regarding Viatel (including,  but not limited to, sales records,
operational  systems customer lists, costs and specifications of Viatel products
and services, know-how, trade secrets, personnel information, research products,
development  plans  or  projects,  investments,   marketing  and  other  company
strategies  and  other  proprietary  information)  which  constitutes  valuable,
special and unique property of Viatel.  You agree that you will not, at any time
or for any  reason or purpose  whatsoever,  make use of,  divulge  or  otherwise
disclose,  directly or indirectly,  any of such information to any person or use
any of such information  without  Viatel's  express prior written  authorization
provided,  however,  that the forgoing  limitation  shall not apply:  (a) to the
extent as may be  required  by law;  (b) to comply  with any  legal  process  or
subpoena (following advance notice to Viatel);  (c) to statements in response to
authorized  inquiry from a court or regulatory body (following advance notice to
Viatel);  and (d) to information  generally  known in the industries  related to
Viatel's  business.  Nothing  herein  shall  prevent you from using your general
skills, general industry knowledge and experience.

          8.  ENGAGING IN  COMPETITION  WITH THE  COMPANY.  Through May 1, 2000,
except as Viatel may otherwise  expressly agree in writing,  you will not become
an employee, owner (except for passive investments of not more than five percent
of the  outstanding  shares of, or any other  equity  interest in any company or
entity   listed  or  traded  on  a  national   securities   exchange  or  in  an
over-the-counter  securities market),  officer, agent, consultant or director of
any firm or  person  which (i)  directly  competes  with  Viatel's  business  of

<PAGE>

developing,  operating or expanding a facilities based  telecommunications voice
or data network,  including, by way of example and not limitation,  any provider
of wireless voice or data services, any internet service provider, or any DSL or
local loop  provider,  that is  competitive  with Viatel's  business  within the
United  States or any European  country in which Viatel  currently  conducts any
business  (including the solicitation of any customer of Viatel on behalf of any
competitor or any other business,  directly,  indirectly on behalf of himself or
any other person or entity) (collectively, "Competitive Activities"). Viatel and
you agree that the scope of your  non-competition  covenant will be as set forth
in this Section 8, notwithstanding any non-competition covenant contained in any
other agreement between you and the Company.  Notwithstanding anything herein to
the contrary: (i) you shall be permitted to make minority investments in private
businesses  in which you are  neither  employed  nor  serving as a  director  or
equivalent  position;  and (ii) this Section 8 shall become null and void on and
after May 1, 2000 and be of no further force or effect.

          9.  NON-SOLICITATION.  For a period of  eighteen  (18) months from the
Termination Date, you shall not solicit,  induce,  counsel,  advise or encourage
either  directly  or  indirectly,  any  employee of Viatel who is employed in an
executive,  managerial,  professional or non-clerical administrative capacity to
leave the employment of Viatel.

          10. NON-DISPARAGEMENT. You and Viatel will not at any time, and Viatel
shall use its best  efforts to ensure  that the Viatel  Persons  will not at any
time,  make any  statement,  whether  written or oral,  or take any other action
which is intended, or could reasonably be expected to, disparage, defame or harm
the reputation (or otherwise cause adverse  publicity) of the other party. In no
event shall any public  statements be made about Viatel or you without the prior
written consent of the other party. You and Viatel also each agree that you will
not assist in any  litigation or  instigation  against the other party except as
required by law.

          11. NON-DISCLOSURE. You and Viatel agree that the terms and conditions
of this Agreement are  confidential  and that each will not, without the express
prior  written  consent of the other party,  in any manner  publish,  publicize,
disclose,  or otherwise make known or permit or cause to be known such terms and
conditions to anyone (other than such party's  prospective  or current  lenders,
financial  advisors  and legal  advisors,  who  shall  agree to be bound by this
paragraph  prior to  disclosure  of the  terms  and  conditions  hereof  to such
persons),  except as required by law, or in any proceeding to enforce then terms
of this  Agreement.  The parties  hereto shall  mutually agree in writing on the
terms of any statement or communication about the circumstances surrounding your
termination  including,  without  limitation,  the terms of any press release or
memo to any officer or employee of Viatel.

          12. REMEDIES.  If you or Viatel should breach each of your or Viatel's
obligations  under the foregoing  paragraphs,  in addition to and not in lieu of
any  other  rights  which  either  party  may  have  at  law  or in  equity  and
contemplated by Section 13 hereof, the non-breaching  party shall have the right
to obtain injunctive  relief, it being acknowledged by the parties that any such
breach would cause  irreparable harm and continuing  injury to the non-breaching
party and that money damages  alone would not provide an adequate  remedy to the
non-breaching  party.  In  the  event  you  breach  in a  material  manner  your
obligations under Sections 6 through 11 hereof, Viatel shall also have the right
to declare (by written  notice to you) and  enforce the  forfeiture  of the cash
amounts  payable  under  Sections  2(c) and 2(d)  hereof.  In the  event  Viatel
breaches  in a material  manner its  obligations  hereunder,  you shall have the
right (by written  notice to Viatel) to cease  performing  any services  through


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<PAGE>

April  1,  2000  and  you  shall  not be  required  to  comply  with  any of the
restrictive  covenants  under Sections 6 through 11 hereof,  provided,  however,
that if you cease to perform  duties  pursuant to this  Section 12, your date of
cessation shall become your Termination Date and you will not be entitled to the
severance under Section 2(d) of this Agreement.

          13. NO WAIVER.  This Agreement  constitutes  the entire  agreement and
understanding  between  you and Viatel and  supersedes  any prior  agreement  or
understanding,  oral or written, between the parties, including, but not limited
to the Employment Agreement (except as specifically referred to herein). None of
the  provisions of this  Agreement  can be waived or modified  except in writing
signed by both parties.  This  Agreement  shall be binding upon and inure to the
benefit of you and your heirs,  legal  administrators  and assigns and  Viatel's
successors   and   assigns   (whether   by  merger,   consolidation,   purchase,
reorganization,  sale of  stock,  sale of  assets,  liquidation  or  otherwise).
Furthermore,  there are no agreements,  covenants or  understandings  other than
those contained  herein except as govern the  compensation and benefit plans and
arrangements set forth herein.

          14. SEVERABILITY.  If any term or provision of this Agreement shall be
held  invalid or  unenforceable,  the  remaining  terms and  provisions  of this
Agreement shall not be affected thereby and (i) such provision shall be reformed
to the minimum extent  necessary to be valid while  preserving the intent of the
parties as expressed  herein,  or (ii) if such provision  cannot be so reformed,
such provision shall be severed from this Agreement and an equitable  adjustment
shall be made to this  Agreement  (including,  without  limitation,  addition of
necessary  further  provisions  to this  Agreement)  so as to give effect to the
intent as so expressed  and the  benefits so provided.  Neither such holding nor
such   reformation  nor  severance  shall  affect  or  impair  the  legality  or
enforceability of any other provision of this Agreement.

          15.  REVOCATION.  You  acknowledge  and  agree  that by  signing  this
Agreement,  you understand that you  voluntarily  waive the right to revoke this
Agreement  during  the seven  (7) day  period  following  the  execution  of the
Agreement.

          16.  MISCELLANEOUS.  In the event that Viatel fails to pay any amounts
provided  hereunder or either  party  otherwise  breaches any  provision of this
Agreement, either in whole or in part, the non-breaching party shall be entitled
to recover  from the other  party,  in addition  to the  recovery of its damages
and/or other relief, any costs,  including reasonable  attorneys' fees, incurred
or reasonably  expected to be incurred in instituting,  prosecuting or defending
any action arising by reason of such failure or the breach of this Agreement.

          17. TAX WITHHOLDING.  Solely to the extent that any payment  hereunder
is subject to  withholding  for federal,  state or local income taxes or federal
employment  taxes,  Viatel agrees to withhold the minimum  amount of withholding
taxes  required by law.  With  respect to the shares of  Restricted  Stock which
become  vested  hereunder,  Viatel  shall  reduce the amount of shares of Common
Stock  otherwise  deliverable  to you to cover the minimum amount of withholding
taxes  required  by law.  Viatel  represents  and  warrants  that,  prior to the
Effective  Date, it shall have obtained  approval by Viatel's Board of Directors
or a compensation  committee of such board which consists solely of at least two
(2) non-employee  directors,  of the reduction of such shares of Common Stock so
that it will be  treated as an exempt  "disposition  to the  issuer"  under Rule
16b-3 promulgated under Section 16(b) of the Exchange Act.


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<PAGE>

          18.  TAX  INDEMNITY.  Viatel  shall  select  and  retain a law firm or
accounting firm with a national  reputation  (which may be Viatel's  current law
firm or auditors) to determine whether you have a reasonable  reporting position
that the  acceleration of stock options under your employment  agreement,  dated
May 3, 1999 with Destia Communications, Inc., (the "Payments") is not subject to
the excise tax imposed under Sections 280G and 4999 of the Internal Revenue Code
of 1986, as amended (the "Code"). The advice of such law firm or accounting firm
shall be provided  to you in writing  within  thirty (30) days of the  Effective
Date.  Upon  receipt  of such  written  advice,  you agree to take a  consistent
position with such advice.  Notwithstanding  anything herein to the contrary, in
the event  that all or any  portion of the  Payments  will be or are found to be
subject to the tax imposed under Sections 280G and 4999 of the Code (the "Excise
Tax"), Viatel shall indemnify you up to $3 million for, and, if required,  shall
pay, the Excise Tax plus all interest and penalties  resulting  from the payment
of or failure to pay the Excise Tax.

          19. INDEMNIFICATION;  D&O INSURANCE. Viatel hereby agrees to indemnify
you  against  any  and all  expenses  (including  attorney's  fees  and  costs),
liabilities,  costs, damages,  judgments,  fines and amounts paid in settlement,
actually and reasonably  incurred by you, to the fullest extent now or hereafter
permitted  by law,  in  connection  with any  threatened,  pending or  completed
action,  suit  or  proceeding,   whether  civil,  criminal,   administrative  or
investigative, brought or threatened to be brought against you by reason of your
performance as a director,  officer,  employee or agent of Viatel. The rights of
indemnification  provided  for herein  shall be not be deemed  exclusive  of any
other rights to which you may be entitled under Viatel's  By-laws or Certificate
of  Incorporation,  and shall inure to the benefit of your heirs,  executors and
administrators.  Any expenses (including  reasonable  attorney's fees and costs)
incurred  by you in  connection  with an  event  for  which  indemnification  is
provided  hereunder  shall be paid  promptly  by Viatel in  advance of the final
disposition of such action, suit or proceeding upon receipt of an undertaking by
you to repay such amount if it shall  ultimately be determined  that you are not
entitled to be indemnified by Viatel as authorized by law.  Viatel will continue
to maintain  Directors' and Officers'  Liability Insurance (the "D&O Insurance")
for you until the sixth  anniversary  of the Effective Date in an amount no less
than the same amount currently provided to Viatel's directors and officers.

          20.  GOVERNING  LAW AND CHOICE OF FORUM.  PURSUANT  TO TITLE 14 OF THE
GENERAL  OBLIGATIONS LAW OF THE STATE OF NEW YORK, THE PARTIES HERETO AGREE THAT
(1) THE RIGHTS AND OBLIGATIONS OF THE PARTIES HEREUNDER SHALL BE GOVERNED BY AND
INTERPRETED, CONSTRUED, AND ENFORCED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE
STATE OF NEW YORK,  EXCEPT TO THE EXTENT THAT FEDERAL LAW MAY GOVERN AND (2) THE
FORUM FOR ANY  DISPUTE  HEREUNDER  SHALL BE IN ANY  FEDERAL  AND/OR  STATE COURT
LOCATED IN NEW YORK  COUNTY,  AND THERE SHALL BE NO DEFENSE TO THE  SELECTION OF
SUCH FORUM BASED ON JURISDICTION, VENUE OR CONVENIENCE. EACH PARTY HERETO HEREBY
IRREVOCABLY  WAIVES ANY OBJECTION TO SUCH  JURISDICTION OR  INCONVENIENT  FORUM.
PLEASE READ THIS AGREEMENT CAREFULLY. BY EXECUTING THIS AGREEMENT, YOU WILL HAVE
WAIVED ANY RIGHT YOU MAY HAVE TO BRING A LAWSUIT OR MAKE ANY LEGAL CLAIM,  KNOWN
OR UNKNOWN,  AGAINST VIATEL,  ITS SUBSIDIARIES OR ANY OF ITS AFFILIATES BASED ON
ANY ACTIONS TAKEN BY VIATEL,  ITS EMPLOYEES OR AGENTS ARISING FROM OR RELATED TO


                                       9
<PAGE>

YOUR EMPLOYMENT WITH VIATEL OR DESTIA OR THE TERMINATION OF SUCH EMPLOYMENT,  UP
TO THE DATE OF THE  EXECUTION OF THIS  AGREEMENT.  WE RECOMMEND  THAT YOU RETAIN
LEGAL COUNSEL TO ADVISE YOU WITH RESPECT TO THE TERMS OF THIS  AGREEMENT AND THE
TERMINATION OF YOUR EMPLOYMENT WITH VIATEL.

                           [INTENTIONALLY LEFT BLANK]





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<PAGE>

          21.  NOTICES.  All  notices,  requests  and  demands  to or  upon  the
respective  parties  must be in writing and may be served by personal  delivery,
facsimile  transmission or certified mail,  return receipt  requested.  All such
notices, requests and demands shall be deemed to be made upon receipt:

          To you:  At the  address  set  forth  above,  with a copy to Andrea S.
Rattner,  Esq., Proskauer Rose LLP, 1585 Broadway, NY, NY 10036 and to Viatel at
685 Third Avenue, 24th Floor, NY, NY 10017, Attention: General Counsel.

          Your signature below signifies your voluntary  acceptance of the terms
of this letter.  Please sign and date both copies of this Agreement in the space
provided. One copy should be retained for your records.

Sincerely,

Viatel, Inc.
                                               Agreed as of the date first
By:/s/ Michael J. Mahoney                      written above:
   -----------------------
   Michael J. Mahoney                          /s/ Alan Levy
   Chief Executive Officer                     ---------------------------------
                                               Alan Levy


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