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                                                                   Exhibit 5.01




                                                                 March 21, 2001

Citigroup Inc.
399 Park Avenue
New York, New York  10043

Ladies and Gentlemen:

         I am Deputy General Counsel of Citigroup Inc., a Delaware corporation
(the "Company"). I refer to the filing by the Company with the Securities and
Exchange Commission (the "Commission") of a Registration Statement on Form S-3
(the "Registration Statement") relating to (i) debt securities of the Company,
which may be senior debt securities (the "Senior Securities") or subordinated
debt securities (the "Subordinated Securities"), (ii) junior subordinated debt
securities (the "Junior Subordinated Debt Securities" and collectively with the
Subordinated Securities and the Senior Securities, the "Debt Securities") issued
in connection with the offering by certain affiliated business trusts of the
Company of capital securities (the "Capital Securities"), certain payments in
respect of which will be guaranteed by the Company (the "Guarantees"), (iii)
warrants ("Index Warrants") representing the right to receive, upon exercise, an
amount in cash that will be determined by reference to prices, yields, levels or
other specified objective measures, (iv) shares of preferred stock of the
Company (the "Preferred Stock"), (v) depositary shares representing entitlement
to all rights and preferences of a share of Preferred Stock of a specified
series (the "Depositary Shares"), and (vi) shares of Common Stock, $.01 par
value per share, of the Company (the "Common Stock"). The Debt Securities, Index
Warrants, Preferred Stock, Depositary Shares and the Common Stock are referred
to herein collectively as the "Offered Securities". The Offered Securities being
registered under the Registration Statement, together with securities registered
under previously filed registration statements, will have an aggregate initial
offering price of up to $30 billion or the equivalent thereof in foreign
currencies and will be offered on a continued or delayed basis pursuant to the
provisions of Rule 415 under the Securities Act of 1933, as amended (the "Act").



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         Unless otherwise provided in any prospectus supplement forming a part
of the Registration Statement relating to a particular series of Debt
Securities, the Senior Securities will be issued under an Indenture dated as of
March 15, 1987, as amended (the "Senior Indenture"), between the Company and The
Bank of New York (the "Senior Trustee"), as Senior Trustee, and the Subordinated
Securities will be issued under an Indenture, the form of which is included as
Exhibit 4.10 to the Registration Statement (the "Subordinated Indenture";
together with the Senior Indenture, the "Indentures"; and each, individually, an
"Indenture"), between the Company and Bank One Trust Company, N.A., as
Subordinated Trustee (each of the Senior Trustee and the Subordinated Trustee, a
"Trustee"). The Index Warrants will be issued under one or more warrant
agreements (each, a "Warrant Agreement"), each to be entered into between the
Company and one or more institutions as identified in the applicable Warrant
Agreement.

         I, or attorneys under my supervision, have examined and am familiar
with originals, or copies certified or otherwise identified to my satisfaction,
of such corporate records of the Company, certificates or documents as I have
deemed appropriate as a basis for the opinions expressed below. In such
examination, I (or such persons) have assumed the legal capacity of all natural
persons, the genuineness of all signatures, the authenticity of all documents
submitted to me (or such persons) as originals, the conformity to original
documents of all documents submitted to me (or such persons) as certified or
photostatic copies and the authenticity of the originals of such copies.

         Based upon and subject to the foregoing and assuming that (i) the
Registration Statement and any amendments thereto (including post-effective
amendments) will have become effective and comply with all applicable laws at
the time the Offered Securities are offered or issued as contemplated by the
Registration Statement; (ii) a Prospectus Supplement, Pricing Supplement and/or
term sheet will have been prepared and filed with the Commission describing the
Offered Securities offered thereby and will comply with all applicable laws;
(iii) all Offered Securities will be issued and sold in compliance with
applicable federal and state laws and in the manner stated in the Registration
Statement and the appropriate Prospectus Supplement, Pricing Supplement and/or
term sheet; (iv) a definitive purchase, underwriting or similar agreement and
any other necessary agreement with respect to any Offered Securities offered or
issued will have been duly authorized and validly executed and delivered by the
parties thereto; (v) the Offered Securities will be sold and delivered at the
price and in accordance with the terms of such agreement and as set forth in the
Registration Statement and the Prospectus Supplement(s), Pricing Supplement(s)
or term sheet(s) referred to therein; and (vi) the Company will authorize the
offering and issuance of the Offered Securities and the terms and conditions
thereof and will take any other appropriate additional corporate action, I am of
the opinion that:



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         1. The Company is a duly incorporated and existing corporation under
the laws of the State of Delaware.

         2. With respect to Debt Securities to be issued under either the Senior
Indenture or Subordinated Indenture, assuming the due authorization, execution,
and delivery of the applicable Indenture by the Trustee, and due execution,
authentication and delivery of the Debt Securities in accordance with the terms
of the applicable Indenture, when such Debt Securities have been issued and sold
in the manner contemplated by the Registration Statement, such Debt Securities
will be legal, valid and binding obligations of the Company and will be entitled
to the benefits of the applicable Indenture.

         3. With respect to the Index Warrants, assuming the (i) due
authorization, execution and delivery of the applicable Warrant Agreement by the
Warrant Agent and (ii) due execution, countersignature and delivery of the Index
Warrants, when such Index Warrants have been issued and sold, such Index
Warrants will be legal, valid and binding obligations of the Company.

         4. Except with respect to Common Stock issuable upon the conversion of
Debt Securities, when the Common Stock has been issued and sold, in the manner
contemplated by the Registration Statement, the Common Stock will be validly
issued, fully paid and nonassessable, assuming the issuance of the Common Stock
has been authorized by all necessary corporate action and that the certificates
evidencing such shares of Common Stock are duly executed and delivered.

         5. With respect to Common Stock issuable upon the conversion of Debt
Securities which are by their terms convertible, such Common Stock will be duly
authorized, validly issued, fully paid and nonassessable, assuming the issuance
of the Common Stock upon conversion of such Debt Securities has been authorized
by all necessary corporate action, that such Debt Securities have been converted
in accordance with their terms and that the certificates evidencing such shares
of Common Stock are duly executed and delivered.

         Insofar as my opinion relates to the validity, binding effect or
enforceability of any agreement or obligation of the Company, it is subject to
applicable bankruptcy, insolvency, reorganization, fraudulent conveyance,
moratorium or other similar laws affecting creditors' rights generally from time
to time in effect and subject to general principles of equity, regardless of
whether such is considered in a proceeding in equity or at law.


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         My opinion is limited to matters governed by the Federal laws of the
United States of America, the laws of the State of New York and the General
Corporation Law of the State of Delaware (including the applicable provisions of
the Delaware Constitution and the reported judicial decisions interpreting the
General Corporation Law of the State of Delaware and such applicable provisions
of the Delaware Constitution). I am not admitted to the practice of law in the
State of Delaware.

         I consent to the use of this opinion in the Registration Statement and
to the reference to my name in the Prospectus constituting a part of such
Registration Statement under the heading "Legal Matters". In giving such
consent, I do not thereby admit that I come within the category of persons whose
consent is required under Section 7 of the Act, or the rules and regulations of
the Securities and Exchange Commission thereunder.



                                                  Very truly yours,

                                                  /s/ Michael A. Ross



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