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                                                                Exhibit No. 2.20


                                Letter Agreement
                            Re: Depositary Agreement



                                                                    May 16, 2003



Citibank, N.A.
Attn: Structured Finance Group
- PF Export Receivables Master Trust
111 Wall Street, 14th Floor
New York, New York 10005

Ladies and Gentlemen:

            Reference is made to the Amended and Restated Trust Deed dated
December 21, 2001 by and among you, U.S. Bank, National Association, Cayman
Islands Branch, as Trustee (the "TRUSTEE") of the PF Export Receivables Master
Trust, Petrobras International Finance Company, as Servicer, and us, Citibank,
N.A. as Registrar, Paying Agent, Transfer Agent and Depositary Bank (as amended
by the Supplemental Trust Deed dated May 16, 2003 and as amended and restated
from time to time, the "TRUST DEED") pursuant to which you have issued
$750,000,000 aggregate principal amount of Senior Trust Certificates and
$150,000,000 aggregate principal amount of Junior Trust Certificates. In
connection with the issuance of the Senior Trust Certificates and the Junior
Trust Certificates, we entered into the Depositary Agreement (the "Agreement")
dated as of December 21, 2001, with you, pursuant to which you were appointed as
Securities Intermediary and agreed to set up and maintain certain trust accounts
and sub-accounts. All capitalized terms used but not otherwise defined in this
letter agreement shall have the meanings ascribed thereto in the Agreement.

            In accordance with the terms of the Trust Deed, we intend to issue
one or more additional series of Senior Trust Certificates and Junior Trust
Certificates. In connection with, and solely in order to effect, such issuance,
we hereby request that you agree that the Agreement shall be hereby amended to
provide that references in the Agreement to any Transaction Document or any
other document or agreement shall be deemed to include references to such
Transaction Document or such other document or agreement as amended, varied,
supplemented or replaced from time to time in accordance with the terms of the
Transaction Documents and to include any appendices, schedules and Exhibits
executed in connection and in accordance therewith.
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            Please acknowledge your receipt of this letter agreement and your
agreement to the terms specified above by executing this letter agreement where
indicated below. This letter agreement shall be governed by, and construed in
accordance with, the law of the State of New York.
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<S>                                             <C>
                                                Very truly yours,

STATE OF NEW YORK         )                     U.S. BANK, NATIONAL ASSOCIATION,
COUNTY OF NEW YORK        )     ss.:            CAYMAN ISLANDS BRANCH,
                                                  as Trustee on behalf of the PF Export
                                                  Receivables Master Trust

Sworn before me this                            By:___________________________________
____ day of __________________, 2003               Name:
                                                   Title:

CONSENTED AND ACKNOWLEDGED:



CITIBANK, N.A.                                  STATE OF NEW YORK       )
   as Securities Intermediary                   COUNTY OF NEW YORK      )       ss.:


By:___________________________________          Sworn before me this
   Name:                                        ____ day of __________________, 2003
   Title:
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<S>                                             <C>
STATE OF NEW YORK         )                     PETROBRAS FINANCE LTD.
COUNTY OF NEW YORK        )     ss.:

Sworn before me this                            By:___________________________________
____ day of __________________, 2003               Name:
                                                   Title:

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Action by the Controlling Parties:

Pursuant to the requirements of Section 7.01(o)(i) of the Amended and Restated
Trust Deed dated December 21, 2001 as amended and restated from time to time
(the "TRUST DEED") among U.S. Bank, National Association, Cayman Islands Branch,
in its capacity as trustee of the PF Export Receivables Master Trust (the
"TRUST"), Citibank, N.A., a national banking association organized under the
laws of the United States of America, in its capacity as Registrar, Paying
Agent, Transfer Agent and Depositary Bank, and Petrobras International Finance
Company, a company organized and existing under the laws of the Cayman Islands,
in its capacity as Servicer under the Servicing Agreement, the undersigned,
being the Controlling Parties with respect to all of the outstanding Senior
Trust Certificates issued by the Trust, do hereby consent to the amendments to
the Depositary Agreement contemplated herein.

Capitalized terms not otherwise defined herein shall have the meaning ascribed
to them under the Trust Deed.

This consent may be executed in two or more counterparts, each of which shall
constitute an original and all of which together shall constitute one and the
same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Action of the Controlling
Parties on the dates set forth following their respective signatures.

AMBAC ASSURANCE CORPORATION



By:___________________________________
   Name:
   Title:

MBIA INSURANCE CORPORATION



By:___________________________________
   Name:
   Title:

XL CAPITAL ASSURANCE INC.



By:___________________________________
   Name:
   Title: