<PAGE>   1
                                                                 Exhibit 4.01

          This Note is a Global Security within the meaning of the Indenture
hereinafter referred to and is registered in the name of the Depository named
below or a nominee of the Depository. This Note is not exchangeable for Notes
registered in the name of a Person other than the Depository or its nominee
except in the limited circumstances described herein and in the Indenture, and
no transfer of this Note (other than a transfer of this Note as a whole by the
Depository to a nominee of the Depository or by a nominee of the Depository to
the Depository or another nominee of the Depository) may be registered except
in the limited circumstances described herein.

          Unless this certificate is presented by an authorized representative
of The Depository Trust Company, a New York corporation (the "Depository"),
to the Company or its agent for registration of transfer, exchange, or payment,
and any certificate issued is registered in the name of Cede & Co. or in
such other name as is requested by an authorized representative of the
Depository (and any payment is made to Cede & Co. or to such other entity as is
requested by an authorized representative of the Depository), ANY TRANSFER,
PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS
WRONGFUL inasmuch as the registered owner hereof, Cede & Co., has an interest
herein.


                                 CITIGROUP INC.
REGISTERED                                                            REGISTERED

                                                              CUSIP: 172967 ____
                                                              ISIN: XS _________
                                                          Common Code: _________

No. R-0001-DTC-_                                                   Yen _________

          CITIGROUP INC., a Delaware corporation (the "Company", which term
includes any successor Person under the Indenture), for value received, hereby
promises to pay to Cede & Co., or registered assigns, the principal sum of
Yen _____ (or such other principal sum as has been most lately endorsed on the
Schedule of Exchanges of Interests hereto) on ________, 20__ and to pay interest
thereon from and including ________, 2000 or from the most recent Interest
Payment Date to which interest has been paid or duly provided for, semi-annually
on ________ and ________ of each year, commencing ________, 200_, at the rate
of ____% per annum, until the principal hereof is paid or made available for
payment. The interest so payable, and punctually paid or duly provided for, on
any Interest Payment Date will, as provided in the Indenture, be paid to the
Person in whose name this Note is registered at the close of business on the
Record Date for such interest, which shall be the ________ or ________ (whether
or not a Business Day) next preceding such Interest Payment Date.
<PAGE>   2
     Any such interest not so punctually paid or duly provided for will
forthwith cease to be payable to the holder on such Record Date and may either
be paid to the Person in whose name this Note is registered at the close of
business on a subsequent Record Date, such subsequent Record Date to be not less
than five days prior to the date of payment of such defaulted interest, notice
whereof shall be given to holders of Notes of this series not less than 15 days
prior to such subsequent Record Date, or be paid at any time in any other lawful
manner not inconsistent with the requirements of any securities exchange on
which the Notes of this series may be listed, and upon such notice as may be
required by such exchange, all as more fully provided in the Indenture.

     Interest hereon will be calculated on the basis of the actual number of
days in the relevant period and a year of 365 days.

     If either a date for payment of principal or interest on the Notes or the
Maturity of the Notes falls on a day that is not a Business Day, the related
payment of principal or interest will be made on the next succeeding Business
Day as if made on the date the payment was due. No interest will accrue on any
amounts payable for the period from and after the date for payment of principal
or interest on the Notes or the Maturity of the Notes. For these purposes,
"Business Day" means any day which is a day on which commercial banks and
foreign exchange markets settle payments and are open for general business
(including dealings in foreign exchange and foreign currency deposits) in (a)
the relevant place of payment and (b) each of The City of New York, Tokyo and
London.

     Payment of the principal of and interest on this Note will be made at the
office or agency of the Company maintained for that purpose in London or The
City of New York in Japanese Yen, provided that holders of interests in this
Note through The Depository Trust Company will receive payment in United States
dollars unless they make an election to receive payment in Japanese Yen in
accordance with the procedures of The Depository Trust Company and the Fiscal
Agency Agreement dated as of          , 2000 (the "Fiscal Agency Agreement"), in
which case the exchange agent under the Fiscal Agency Agreement will convert the
Japanese Yen paid by the Company into U.S. dollars in accordance with the Fiscal
Agency Agreement.

     Reference is hereby made to the further provisions of this Note set forth
on the reverse hereof, which further provisions shall for all purposes have the
same effect as if set forth at this place.

     Unless the certificate of authentication hereon has been executed by the
Trustee or by the authenticating agent on behalf of the Trustee referred to on
the reverse hereof by manual signature, this Note shall not be entitled to any
benefit under the Indenture or be valid or obligatory for any purpose.

<PAGE>   3
     IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed under its corporate seal.

Dated: __________, 2000

                                        CITIGROUP, INC.


                                        By: ___________________________________
                                        Title:



ATTEST:

By: ______________________________
Assistant Secretary
<PAGE>   4
     This is one of the Notes of the series issued under the within-mentioned
Indenture.

Dated: __________, 2000

                                   THE BANK OF NEW YORK,
                                   as Trustee


                                   By: ___________________________________
                                       Name:
                                       Title:

                                   -or

                                   CITIBANK, N.A., LONDON OFFICE,
                                     as Authenticating Agent


                                   By: ___________________________________
                                       Name:
                                       Title:
<PAGE>   5
     This Note is one of a duly authorized issue of Securities of the Company
(the "Notes"), issued and to be issued in one or more series under the
Indenture, dated as of March 15, 1987 (as amended and supplemented to date, the
"Indenture"), between the Company and The Bank of New York, as Trustee (the
"Trustee", which term includes any successor trustee under the Indenture), to
which Indenture and all indentures supplemental thereto reference is hereby made
for a statement of the respective rights, limitations of rights, duties and
immunities thereunder of the Company, the Trustee and the holders of the Notes
and of the terms upon which the Notes are, and are to be, authenticated and
delivered. This Note is one of the series designated on the face hereof,
initially issued in the aggregate principal amount of (Yen
symbol)__,000,000,000.

     So long as the Notes of this series are in the form of Global Securities
only, all Notes of this series will collectively be evidenced (a) by this Global
Note and the Global Note for this series bearing registration number
R-0001-DTC-_ (together, the "DTC Global Notes") and (b) by the Global Security
of this series registered in the name of Citivic Nominees Limited (the
"International Global Note"). The DTC Global Notes and the International Global
Note will at all times collectively represent the aggregate principal amount of
this series outstanding from time to time. If at any time a portion of the
International Global Note is exchanged for an interest in a DTC Global Note, the
principal amount of a DTC Global Note shall be increased by the amount of such
portion, and that DTC Global Note shall be endorsed on the Schedule of Exchanges
of Interests thereto to reflect such principal increase, subject to the
limitation that in no event may the principal amount of a DTC Global Note be
greater than the equivalent in U.S. dollars of $400,000,000. If at any time a
portion of a DTC Global Note is exchanged for an interest in the International
Global Note, the principal amount of that DTC Global Note shall be decreased by
the amount of such portion, and that DTC Global Note shall be endorsed on the
Schedule of Exchanges of Interests thereto to reflect such principal decrease.
To ascertain the U.S. dollar equivalent of the principal amount endorsed on the
Schedule of Exchanges of Interests attached to a DTC Global Note, inquiry shall
be made of the exchange agent under the Fiscal Agency Agreement, and the U.S.
dollar equivalent quoted by such exchange agent (and the date of such quote)
shall be noted on such Schedule of Exchanges of Interests next to the
corresponding Yen amount.

     If an event of default (as defined in the Indenture) with respect to Notes
of this series shall occur and be continuing, the principal of the Notes of
this series may be declared due and payable in the manner and with the effect
provided in the Indenture.

     The Indenture contains provisions for defeasance at any time of the entire
indebtedness of this Note upon compliance by the Company with certain
conditions set forth in Sections 11.03 and 11.04 thereof, which provisions apply
to this Note.

     The Indenture contains provisions permitting the Company and the Trustee,
without the consent of the holders of Securities, to establish, among other
things, the form and terms of any series of Securities issuable thereunder by
one or more supplemental indentures, and, with the consent of the holders of not
less than 66-2/3% in aggregate principal amount of
<PAGE>   6
Securities at the time Outstanding which are affected thereby, to modify
the Indenture or any supplemental indenture or the rights of the holders of
Securities of such series to be affected, provided that no such modification
will (x) extend the fixed maturity of any Securities, reduce the rate or extend
the time of payment of interest thereon, reduce the principal amount thereof or
the premium, if any, thereon, reduce the amount of the principal of Original
Issue Discount Securities payable on any date, change the currency in which
Securities are payable, or impair the right to institute suit for the
enforcement of any such payment on or after the maturity thereof, without the
consent of the holder of each Security so affected, or (y) reduce the aforesaid
percentage of Securities of any series the consent of the holders of which is
required for any such modification without the consent of the holders of all
Securities of such series then Outstanding, or (z) modify, without the written
consent of the Trustee, the rights, duties or immunities of the Trustee.

     No reference herein to the Indenture and no provision of this Note or of
the Indenture shall alter or impair the obligation of the Company, which is
absolute and unconditional, to pay the principal of and interest on this Note
at the times, place and rate, and in the coin or currency, herein prescribed.

     This Note is a Global Security registered in the name of a nominee of the
Depository. This Note is exchangeable for Notes registered in the name of a
person other than the Depository or its nominee only in the limited
circumstances hereinafter described. Unless and until it is exchanged in whole
or in part for definitive Notes in certificated form, this Note may not be
transferred except as a whole by the Depository to a nominee of the Depository
or by a nominee of the Depository to the Depository or another nominee of the
Depository.

     The Notes represented by this Global Security are exchangeable for
definitive Notes in certificated form of like tenor as such Notes in
denominations of Yen 1,000,000 and integral multiples thereof only if (i) the
Depository notifies the Company that it is unwilling or unable to continue as
Depository for the DTC Global Notes or (ii) the Depository ceases to be a
clearing agency registered under the Securities Exchange Act of 1934, as
amended, or (iii) both the Euroclear System and Clearstream Banking, societe
anonyme, notify the Company that they are unwilling or unable to continue as a
clearing system for the International Global Note or (iv) the Company in its
sole discretion decides to allow the Notes to be exchanged for definitive Notes
in registered form. Any Notes that are exchangeable pursuant to the preceding
sentence are exchangeable for certificated Notes issuable in authorized
denominations and registered in such names as the Depository shall direct. As
provided in the Indenture and subject to certain limitations therein set forth,
the transfer of definitive Notes in certificated form is registrable in the
register maintained by the Company for such purpose, upon surrender of the
definitive Note for registration of transfer at the office or agency of the
Company in any place where the principal of and interest on the definitive Note
are payable, duly endorsed by, or accompanied by a written instrument of
transfer in form satisfactory to the Company and the registrar duly executed
by, the holder thereof or his attorney duly authorized in writing, and
thereupon one or more new Notes of this series and of like tenor, of authorized
denominations and for the same aggregate principal amount, will be issued to
the designated transferee or transferees. Subject to the foregoing, this Note
is not exchangeable, except for a Global Security or Global Securities of

<PAGE>   7
this issue of the same principal amount to be registered in the name of the
Depository or its nominee.

          No service charge shall be made for any such registration of transfer
or exchange, but the Company may require payment of a sum sufficient to cover
any tax or other governmental charge payable in connection therewith.

          Prior to due presentment of this Note for registration of transfer,
the Company, the Trustee and any agent of the Company or the Trustee may treat
the Person in whose name this Note is registered as the owner hereof for all
purposes, whether or not this Note be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

          The Company will pay additional amounts ("Additional Amounts") to the
beneficial owner of any Note that is a non-United States person in order to
ensure that every net payment on such Note will not be less, due to payment of
U.S. withholding tax, than the amount then due and payable. For this purpose, a
"net payment" on a Note means a payment by the Company or a paying agent,
including payment of principal and interest, after deduction for any present or
future tax, assessment or other governmental charge of the United Sates. These
Additional Amounts will constitute additional interest on the Note.

          The Company will not be required to pay Additional Amounts, however,
in any of the circumstances described in items (1) through (12) below.

          (1)       Additional Amounts will not be payable if a payment on a
                    Note is reduced as a result of any tax, assessment or other
                    governmental charge that is imposed or withheld solely by
                    reason of the beneficial owner:

                    (a)       having a relationship with the United States as a
                              citizen, resident or otherwise;

                    (b)       having had such a relationship in the past or

                    (c)       being considered as having had such a
                              relationship.

          (2)       Additional Amounts will not be payable if a payment on a
                    Note is reduced as a result of any tax, assessment or other
                    governmental charge that is imposed or withheld solely by
                    reason of the beneficial owner:

                    (a)       being treated as present in or engaged in a trade
                              or business in the United States;

                    (b)       being treated as having been present in or
                              engaged in a trade or business in the United
                              States in the past or

                    (c)       having or having had a permanent establishment in
                              the United States.

          (3)       Additional Amounts will not be payable if a payment on a
                    Note is reduced as a result of any tax, assessment or other
                    governmental charge that is imposed or withheld solely by
                    reason of the beneficial owner being or having been a:

                    (a)       personal holding company;

                    (b)       foreign personal holding company;
<PAGE>   8
          (c) foreign private foundation or other foreign tax-exempt
              organization;

          (d) passive foreign investment company;

          (e) controlled foreign corporation or

          (f) corporation which has
              accumulated earnings to avoid United States federal income tax.

     (4)  Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any tax, assessment or other governmental
          charge that is imposed or withheld solely by reason of the beneficial
          owner owning or having owned, actually or constructively, 10 percent
          or more of the total combined voting power of all classes of stock of
          the Company entitled to vote.

For purposes of item (1) through (4) above, "beneficial owner" means a
fiduciary, settlor, beneficiary, member or shareholder of the holder if the
holder is an estate, trust, partnership, limited liability company, corporation
or other entity, or a person holding a power over an estate or trust
administered by a fiduciary holder.

     (5)  Additional Amounts will not be payable to any beneficial owner of a
          Note that is a:

          (a) fiduciary;
          (b) partnership;
          (c) limited liability company or
          (d) other fiscally transparent entity
              or that is not the sole beneficial owner of the Note, or any
              portion of the Note. However, this exception to the obligation to
              pay Additional Amounts will only apply to the extent that a
              beneficiary or settlor in relation to the fiduciary, or a
              beneficial owner or member of the partnership, limited liability
              company or other fiscally transparent entity, would not have been
              entitled to the payment of an Additional Amount had the
              beneficiary, settlor, beneficial owner or member received directly
              its beneficial or distributive share of the payment.

     (6)  Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any tax, assessment or other governmental
          charge that is imposed or withheld solely by reason of the failure of
          the beneficial owner or any other person to comply with applicable
          certification, identification, documentation or other information
          reporting requirements. This exception to the obligation to pay
          Additional Amounts will only apply if compliance with such reporting
          requirements is required by statute or regulation of the United States
          or by an applicable income tax treaty to which the United States is a
          party as a precondition to exemption from such tax, assessment or
          other governmental charge.

     (7)  Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any tax, assessment or other governmental
          charge that is collected or imposed by any method other than by
          withholding from a payment on a Note by the Company or a paying agent.
<PAGE>   9
     (8)  Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any tax, assessment or other governmental
          charge that is imposed or withheld by reason of a change in law,
          regulation, or administrative or judicial interpretation that becomes
          effective more than 15 days after the payment becomes due or is duly
          provided for, whichever occurs later.

     (9)  Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any tax, assessment or other governmental
          charge that is imposed or withheld by reason of the presentation by
          the beneficial owner of a Note for payment more than 30 days after the
          date on which such payment becomes due or is duly provided for,
          whichever occurs later.

     (10) Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any:

          (a)  estate tax;

          (b)  inheritance tax;

          (c)  gift tax;

          (d)  sales tax;

          (e)  excise tax;

          (f)  transfer tax;

          (g)  wealth tax;

          (h)  personal property tax or

          (i)  any similar tax, assessment or other governmental charge.

     (11) Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any tax, assessment, or other governmental
          charge required to be withheld by any paying agent from a payment of
          principal or interest on a Note if such payment can be made without
          such withholding by any other paying agent.

     (12) Additional Amounts will not be payable if a payment on a Note is
          reduced as a result of any combination of items (1) through (11)
          above.

     Except as specifically provided herein, the Company will not be required to
make any payment of any tax, assessment or other governmental charge imposed by
any government or a political subdivision or taxing authority of such
government.

     As used in this Note, "United States person" means:

     (a)  any individual who is a citizen or resident of the United States;

     (b)  any corporation, partnership or other entity created or organized in
          or under the laws of the United States;

     (c)  any estate if the income of such estate falls within the federal
          income tax jurisdiction of the United States regardless of the source
          of such income and

     (d)  any trust if a United States court is able to exercise primary
          supervision over its administration and one or more United States
          persons have the authority to control all of the substantial decisions
          of the trust.

<PAGE>   10
     Additionally, "non-United States person" means a person who is not a
United States person, and "United States" means the United States of America,
including the States and the District of Columbia, its territories, its
possessions and other areas within its jurisdiction.

     Except as provided below, the Notes may not be redeemed prior to maturity.
     (1)  The Company may, at its option, redeem the Notes if:
         (a)  the Company becomes or will become obligated to pay Additional
              Amounts as described above;
         (b)  the obligation to pay Additional Amounts arises as a result of
              any change in the laws, regulations or rulings of the United
              States, or an official position regarding the application or
              interpretation of such laws, regulations or rulings, which
              change is announced or becomes effective on or after     , 2000
              and
         (c)  the Company determines, in its business judgment, that the
              obligation to pay such Additional Amounts cannot be avoided by
              the use of reasonable measures available to it, other than
              substituting the obligor under the Notes or taking any action
              that would entail a material cost to the Company.

     (2) The Company may also redeem the Notes, at its option, if:
         (a)  any act is taken by a taxing authority of the United States on or
              after     , 2000, whether or not such act is taken in relation to
              the Company or any affiliate, that results in a substantial
              probability that the Company will or may be required to pay
              Additional Amounts as described under above;
         (b)  the Company determines, in its business judgment, that the
              obligation to pay such Additional Amounts cannot be avoided by
              the use of reasonable measures available to it, other than
              substituting the obligor under the Notes or taking any action that
              would entail a material cost to the Company and
         (c)  the Company receives an opinion of independent counsel to the
              effect that an act taken by a taxing authority of the United
              States results in a substantial probability that the Company will
              or may be required to pay the Additional Amounts described under
              above, and delivers to the Trustee a certificate, signed by a
              duly authorized officer, stating that based on such opinion the
              Company is entitled to redeem the Notes pursuant to their terms.

Any redemption of the Notes as set forth in clauses (1) or (2) above shall be in
whole, and not in part, and will be made at a redemption price equal to 100% of
the principal amount of the Notes Outstanding plus accrued interest thereon to
the date of redemption. Holders shall be given not less than 30 days nor more
than 60 days prior notice by the Trustee of the date fixed for such redemption.

         All terms used in this Note which are defined in the Indenture shall
have the meanings assigned to them in the Indenture. The Notes are governed by
the laws of the State of New York.
<PAGE>   11
                       SCHEDULE OF EXCHANGES OF INTERESTS

     The following exchanges of a part of this Note for an interest in another
Global Security or for a certificated Note, or exchanges of a part of another
Global Security or certificated Note for an interest in this Note, have been
made:


<TABLE>
<CAPTION>
                                                    Principal Amount of     Signature of
          Amount of decrease   Amount of increase   this Note following     Authorized
          in Principal Amount  in Principal Amount  such decrease (or       Officer of
Date of   of this Note         of this Note         increase)               Trustee or
Exchange                                                                    Fiscal Agent
--------  -------------------  -------------------  -------------------     -------------
<S>       <C>                  <C>                  <C>                    <C>
________, 2000 (original issuance)                  Yen__________           _____________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

</TABLE>

*  This Schedule may be used by the Trustee, Paying Agent, Fiscal Agent or other
   agent of the Company in respect of this Note, and, if so used, shall be
   deemed a part thereof for all purposes.