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                                                                    EXHIBIT 10.1

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                        AMENDED AND RESTATED DEMAND NOTE
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THIS AMENDED AND RESTATED DEMAND NOTE (THIS "DEMAND NOTE") IS AN AMENDMENT AND
RESTATEMENT BUT NOT A NOVATION OF EACH OF THE ORIGINAL PROMISSORY NOTE AND THE
ORIGINAL STANDBY NOTE, AS EACH IS DEFINED HEREIN.


Initial Principal Amount: $97,434,710.13                       January 25, 2001

FOR VALUE RECEIVED on January 25, 2001, (the "EFFECTIVE DATE"), the undersigned,
STAR TELECOMMUNICATIONS, INC., with its chief executive offices located at 223
East De La Guerra, Santa Barbara, California, 93101, a Delaware corporation
(together with its successors and assigns, the "MAKER"), promises to pay ON
DEMAND in immediately available funds and to the order of MCI WORLDCOM NETWORK
SERVICES, INC., with offices located at 6929 N. Lakewood Avenue, Mail Drop
5.2-510, Tulsa, Oklahoma 74117 ("HOLDER"), the principal sum of NINETY SEVEN
MILLION, FOUR HUNDRED THIRTY-FOUR THOUSAND, SEVEN HUNDRED TEN AND 13/100 DOLLARS
($97,434,710.13), together with interest on the unpaid principal amount of this
Demand Note from the Effective Date, accruing at a rate of eighteen percent
(18%) PER ANNUM, based on a year of 365 or 366 days, as the case may be, and
actual days elapsed

Maker shall be permitted to make voluntary prepayments of principal under this
Demand Note, without penalty on any such payment date. The acceptance by Holder
of any payment hereunder that is less than payment in full of all amounts due
and payable at the time of such payment shall not constitute a waiver of the
right to exercise any of Holder's rights and remedies hereunder at that time, or
at any subsequent time, or nullify any prior exercise of any such right or
remedy without the express written consent of Holder. The acceptance by Holder
of this Demand Note shall not constitute a waiver by Holder of any of its
rights, whether under the Workout Agreement or any other WorldCom Document, as
each is defined below, or at law or in equity, nor shall the delivery by Maker
of this Demand Note constitute a satisfaction of any of Maker's obligations to
Holder.

All payments and prepayments to be made in respect of principal, interest or
other amounts due from the Maker under this Demand Note shall be payable to
Holder at the address set forth above for Holder, and directed to the attention
of Robert S. Vetera, Vice President of Corporate Credit, or at such other place
as Holder may designate in writing, in lawful money of the United States of
America in immediately available funds without setoff, counterclaim or other
deduction of any nature. The Maker expressly waives presentment, notice, protest
and all other demands and notices in connection with the delivery, acceptance,
performance, default or enforcement of this Demand Note, and an action for any
amounts due and unpaid shall therefore accrue immediately. THE MAKER
ACKNOWLEDGES AND AGREES THAT THE HOLDER MAY AT ANY TIME AND IN ITS SOLE
DISCRETION DEMAND PAYMENT OF ALL AMOUNTS OUTSTANDING UNDER THIS DEMAND NOTE
WITHOUT PRIOR NOTICE TO THE MAKER.

If any payment of principal or interest under this Demand Note becomes due on a
day which is a Saturday, Sunday or other day on which lending institutions are
authorized or obligated to close in Tulsa, Oklahoma or Santa Barbara,
California, such payment shall nevertheless be immediately due and payable.

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Any and all references to the Original Promissory Note or the Original Standby
Note contained in:

         1.       that certain Workout Agreement dated as of April 12, 2000
                  between and among STAR TELECOMMUNICATIONS, INC., PT-1
                  COMMUNICATIONS, INC., HELVEY COM, LLC, CEO CALIFORNIA
                  TELECOMMUNICATIONS, INC., CEO TELECOMMUNICATIONS, INC.,
                  LUCIUS ENTERPRISES, INC., AS TELECOMMUNICATIONS, INC., PT-1
                  LONG DISTANCE, INC., PT-1 HOLDINGS I, INC., PHONETIME
                  TECHNOLOGIES, INC., PT-1 HOLDINGS II, INC., NATIONWIDE
                  DISTRIBUTORS, INC., TECHNOLOGY LEASING, INC., INVESTMENT
                  SERVICES, INC., AND PT-1 COMMUNICATIONS PUERTO RICO, INC.,
                  as amended through the date hereof (and as may be further
                  amended or supplemented from time to time hereafter)
                  (collectively, the "WORKOUT AGREEMENT");

         2.       the "WorldCom Documents" as defined in the Workout Agreement;
                  and

         3.       any document or agreement delivered pursuant to or in
                  connection with the Workout Agreement,

shall be deemed to mean the Original Promissory Note or the Original Standby
Note (as the case may be) as amended, supplemented, modified and restated
hereby, and as may be further amended, modified, supplemented or extended from
time to time. The Maker hereby confirms that any collateral or security provided
for one or more of the Original Promissory Note or the Original Standby Note,
including, but not limited to, liens, security interests, mortgages and pledges
of tangible or intangible property and assets granted by the Maker or any third
parties shall continue unimpaired and in full force and effect, and shall
support this Demand Note in the same manner as such collateral was intended to
support the Original Promissory Note or the Original Standby Note (as the case
may be).

All notices and other communications required or permitted to be made to the
Maker or Holder, as the case may be, hereunder shall be made in writing and will
be deemed delivered when received by the other party, whether by messenger,
telex, telecopier, overnight courier, mail, or otherwise, which notice shall be
delivered to any officer, director or authorized representative of the Maker or
Holder, or to the respective addresses of Maker and Holder set forth in the
Workout Agreement, or such other address as each party may notify the other
party in writing from time to time.

Upon the occurrence of any one of the following events (each an "EVENT OF
DEFAULT"), the entire principal amount outstanding hereunder together with
accrued interest, shall: (i) at the option of Holder in the case of the "Events
of Default" set forth in (a) through (c), below; or (ii) without the necessity
for any demand, notice or action by Holder in the case of the "Events of
Default" set forth in (d) through (f), below, become immediately due and payable
in full and Holder may, without further delay, undertake any one or more of the
actions and become entitled to any of the remedies specified in this Demand Note
or any other "WorldCom Document" or which are otherwise available at law or in
equity:

         (a)      Failure of Maker to pay any installment of principal or
                  interest or any other sum on the date when it is due under
                  this Demand Note; or

         (b)      Maker fails to perform or observe any of its other covenants
                  or agreements under this Demand Note, the Workout Agreement,
                  or any of the WorldCom Documents, or otherwise fails to
                  perform or observe any of its covenants or agreements under
                  any agreement,

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                  contract, instrument, note, and any amendments, extensions,
                  renewals or replacements to or of any of the foregoing,
                  whether presently existing or hereafter arising, and such
                  default continues beyond any applicable grace, waiver or cure
                  period set forth therein, if any; or

         (c)      Any representation or warranty made by the Maker pursuant to
                  this Demand Note or any other WorldCom Document shall prove to
                  have been false or misleading in any material respect as of
                  the time when made; or

         (d)      If Maker, or any guarantor or surety of the obligations
                  evidenced by this Demand Note, shall make a general assignment
                  for the benefit of its respective creditors, or shall admit in
                  writing its inability to pay its debts as they become due, or
                  shall file a petition in bankruptcy, or shall be adjudicated
                  bankrupt or insolvent, or shall file a petition seeking any
                  relief under any present or future statute, law or regulation
                  relating to bankruptcy or insolvency or shall file an answer
                  admitting or not contesting the material allegations of a
                  petition filed against it in any such proceeding or shall seek
                  or consent to or acquiesce in the appointment of any trustee
                  or receiver of itself or any material part of its respective
                  properties; or

         (e)      If any proceeding against Maker seeking any relief under any
                  present or future statute, law or regulation relating to
                  bankruptcy or insolvency shall have been filed or shall be
                  prosecuted or if an appointment shall have been made without
                  the consent or acquiescence of Maker or of any material part
                  of their respective properties and such appointment shall not
                  have been vacated; or

         (f)      A writ or warrant of attachment, garnishment, execution,
                  distraint or similar process shall have been issued against
                  Maker or any of its properties involving a sum in excess of
                  $50,000 which shall have remained undischarged or unstayed for
                  a period of thirty (30) days.

If an Event of Default occurs, then, Maker agrees to indemnify and hold Holder
harmless from any and all reasonable fees and expenses of Holder's attorneys,
accountants, appraisers, consultants, engineers and other professional,
paraprofessional or non-professional fees and expenses incurred by Holder in
collecting the obligations evidenced hereby, or in protecting or otherwise
enforcing any of its rights under this Demand Note or any of the other WorldCom
Documents, or in the prosecution or defense of any action related to this Demand
Note or any of the WorldCom Documents, or the preservation, maintenance,
disposition or liquidation of any collateral securing the Maker's obligations
evidenced by this Demand Note, or any portion thereof.

The exercise of any remedy hereunder or under any other WorldCom Document shall
not be construed as a waiver by Holder of any remedy available to Holder under
any other agreement, document, equity or applicable law. HOLDER HEREBY EXPRESSLY
RESERVES ALL OF ITS RIGHTS UNDER SUCH AGREEMENTS, DOCUMENTS, EQUITY AND
APPLICABLE LAW.

In the event the rate of interest provided for in this Demand Note is finally
determined by any government or political subdivision or any agency, authority,
bureau, central bank, commission, department or instrumentality of either, or
any court, tribunal, grand jury or arbitrator, in each case whether foreign or
domestic (each as "OFFICIAL BODY"), to exceed the maximum rate of interest
permitted by applicable usury

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or similar law (including common law), constitution, statute, treaty,
regulation, rule, ordinance, order, injunction, writ, decree or award of any
Official Body ("LAW"), their or its application will be suspended and there will
be charged instead the maximum rate of interest permitted by such Laws. Interest
at the rates applicable to this Demand Note as set forth herein shall continue
to accrue on any judgment entered on this Demand Note until the judgment
together with interest and costs has been paid in full.

This Demand Note is governed by, and will be construed and enforced in
accordance with, the laws of the State of Oklahoma without regard to principles
of conflicts of law in the State of Oklahoma. The Maker consents to the
exclusive jurisdiction and venue of the Federal and State courts located in
Tulsa, Oklahoma with respect to any suit arising out of, relating to, or
mentioning this Demand Note. The terms of this Demand Note shall be binding upon
and inure to the benefit of the successors and assigns of Holder, and shall not
be assignable by Maker, unless Holder has provided its prior, written consent to
such assignment.

This Demand Note is given by Maker in consideration of the agreements,
accommodations and understandings previously made by Holder pursuant to the
Original Promissory Note, the Original Standby Note, the WorldCom Documents and
the documents and agreements related thereto, and in consideration of the
agreements, accommodations and understandings herein granted to the Maker by the
Holder. This Demand Note is given to Holder in exchange for and in substitution
of the Original Promissory Note and the Original Standby Note.

This Demand Note amends and restates, in its entirety, but is not a novation of,
each of that certain:

         1.       Promissory Note dated April 12, 2000, given by Maker payable
                  to the order of the Holder in the original principal amount of
                  FIFTY-SIX MILLION SEVENTEEN THOUSAND SIX HUNDRED NINETY-EIGHT
                  AND 87/100 DOLLARS ($56,017, 698.87), plus interest as stated
                  therein, as amended by that certain Amendment No.1 thereto
                  dated as of July 31, 2000, and as further amended by that
                  certain Amendment No.2 thereto dated as of August 15, 2000,
                  and as further amended by that certain Amendment No.3 thereto
                  dated as of October 27, 2000, and as further amended by that
                  certain Amendment No.4 thereto dated as of December 14, 2000
                  (collectively, the "ORIGINAL PROMISSORY NOTE"); and

         2.       Standby Term Loan Note dated June 30, 2000, given by Maker
                  payable to the order of the Holder in the original principal
                  amount of THIRTY MILLION AND 00/100 DOLLARS ($30,000,000.00),
                  plus interest as stated therein, as amended by that certain
                  Amendment No.1 thereto dated as of July 31, 2000, and as
                  further amended by that certain Amendment No.2 thereto dated
                  as of August 15, 2000, and as further amended by that certain
                  Amendment No.3 thereto dated as of October 27, 2000, and as
                  further amended by that certain Amendment No.4 thereto dated
                  as of December 14, 2000 (collectively, the "ORIGINAL STANDBY
                  NOTE").

EACH OF MAKER AND HOLDER EXPRESSLY, KNOWINGLY AND VOLUNTARILY WAIVES ALL BENEFIT
AND ADVANTAGE OF ANY RIGHT TO A TRIAL BY JURY, AND NEITHER WILL AT ANY TIME
INSIST UPON, OR PLEAD OR IN ANY MANNER WHATSOEVER CLAIM OR TAKE THE BENEFIT OR
ADVANTAGE OF A TRIAL BY JURY IN ANY ACTION ARISING IN CONNECTION HEREWITH OR THE
OTHER WORLDCOM DOCUMENTS.

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                         INITIAL: ____ MAKER ____ HOLDER

IN WITNESS WHEREOF, and intending to be legally bound, the Maker has executed,
issued and delivered this Amended and Restated Demand Note as of the day and
year first above written.


ATTEST:                                  STAR TELECOMMUNICATIONS, INC.

By: /s/ David Vaun Crumly                By: /s/ Timothy F. Sylvester
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Name:  David Vaun Crumly                 Name:  Timothy F. Sylvester
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Title: Executive Vice President --       Title: Executive Vice President
       Sales & Marketing                        and General Counsel