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                                                                     Exhibit 4.1

December 30, 1999

Name
Address
Address

To:  All holders of
     Convertible Notes of
     American TeleSource International, Inc. ("ATSI" or "the Company")
     Issued March 17, 1997

Dear NAME:

     According to your records, you are the holder of $25,000 of Convertible
Notes of ATSI which are scheduled to mature on March 17, 2000. On that date, the
principal and accrued interest since the date of issuance is scheduled to be
paid to you.

     The Board of Directors of ATSI has agreed to offer you the following
opportunities in lieu of receiving the cash payment due you on the scheduled
maturity date:

     a.)   The right to convert outstanding warrants to purchase the common
           stock of ATSI held by you against the outstanding amounts owed to you
           by ATSI; and

     b)    The right to convert any remaining outstanding principal and interest
           owed to you, after exercising your rights under a) above, into common
           stock of ATSI.

The above-mentioned transactions would take place effective January 31, 2000.
As of that date, our records indicate that the total principal and interest owed
you under the Convertible Note(s) will total $33,076.

     The price at which your balance would be converted under b) above will
equal  a 20% discount to the average closing price during the ten trading days
up through, and including, January 31, 2000.

     This offer represents a private offering of securities by ATSI, and we
have therefore enclosed with this letter a Confidential Information Memorandum
which should be reviewed by you prior to making your decision regarding the
opportunity being presented to you.  A subscription agreement has also been
included which must be completed by anyone deciding to exercise his option under
b) above.  Any stock received as a result of exercising option a) above will be
freely tradable as the stock underlying outstanding options has been registered.
The common stock under b) above will not be registered, and may not be traded
except pursuant to Rule 144 (or other exemption from registration that may be
available to you).  Rule 144 generally requires you to hold the stock for at
least one year before it may be sold.  After one

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year, the stock may be sold in a "qualified brokers transaction," as defined in
Rule 144; after two years, the stock may be sold free from restrictions.

     This offer is being made to all Convertible Noteholders as a class.  Your
rights under a) and b) may be exercised individually, and are not subject to
action as a group.  Your rights under a) and b) above must be exercised in full
should you choose to do so; partial exercises will not be allowed.  The option
to exercise your rights under a) and b) above must be received by the Company by
January 17, 2000.  A form has been attached for you to indicate your decision to
exercise, or not exercise, your rights.

     The Company encourages each Convertible Noteholder to exercise his rights
under a) and b) above.   Funds will be raised externally in order to pay
Convertible Noteholders who do not exercise their rights per this letter.  Each
Convertible Noteholder is encouraged to call Doug Saathoff, ATSI CFO, at (210)
547-1029 in order to discuss the proposed transaction.

Sincerely,
AMERICAN TELESOURCE INTERNATIONAL, INC.