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                                                                    EXHIBIT 25-I

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                                   FORM T-1
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                           STATEMENT OF ELIGIBILITY
                  UNDER THE TRUST INDENTURE ACT OF 1939 OF A
                   CORPORATION DESIGNATED TO ACT AS TRUSTEE

                     CHECK IF AN APPLICATION TO DETERMINE
                     ELIGIBILITY OF A TRUSTEE PURSUANT TO
                           SECTION 305(b)(2)    [_]

                          ___________________________

                             THE BANK OF NEW YORK
              (Exact name of trustee as specified in its charter)


New York                                               13-5160382
(State of incorporation                                (I.R.S. employer
if not a U.S. national bank)                           identification no.)

One Wall Street, New York, N.Y.                        10286
(Address of principal executive offices)               (Zip code)


                          ___________________________

                          Phillips Petroleum Company
              (Exact name of obligor as specified in its charter)

Delaware                                               73-0400345
(State or other jurisdiction of                        (I.R.S. employer
incorporation or organization)                         identification no.)


Phillips Petroleum Company
Phillips Building                                      74004
Bartlesville, Oklahoma                                 (Zip code)
(Address of principal executive offices)

                          ___________________________

          Guarantee of Preferred Securities of Phillips 66 Capital VI
                      (Title of the indenture securities)

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1.   General information.  Furnish the following information as to the Trustee:

     (a)  Name and address of each examining or supervising authority to which
          it is subject.

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                Name                                           Address
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     Superintendent of Banks of the State of         2 Rector Street, New York,
     New York                                        N.Y. 10006, and Albany,
                                                     N.Y. 12203

     Federal Reserve Bank of New York                33 Liberty Plaza, New
                                                     York, N.Y. 10045

     Federal Deposit Insurance Corporation           Washington, D.C. 20429

     New York Clearing House Association             New York, New York 10005

     (b)  Whether it is authorized to exercise corporate trust powers.

     Yes.

2.   Affiliations with Obligor.

     If the obligor is an affiliate of the trustee, describe each such
     affiliation.

     None.

16.  List of Exhibits.

     Exhibits identified in parentheses below, on file with the Commission, are
     incorporated herein by reference as an exhibit hereto, pursuant to Rule 7a-
     29 under the Trust Indenture Act of 1939 (the "Act") and 17 C.F.R.
     229.10(d).

     1.   A copy of the Organization Certificate of The Bank of New York
          (formerly Irving Trust Company) as now in effect, which contains the
          authority to commence business and a grant of powers to exercise
          corporate trust powers. (Exhibit 1 to Amendment No. 1 to Form T-1
          filed with Registration Statement No. 33-6215, Exhibits 1a and 1b to
          Form T-1 filed with Registration Statement No. 33-21672 and Exhibit 1
          to Form T-1 filed with Registration Statement No. 33-29637.)

     4.   A copy of the existing By-laws of the Trustee. (Exhibit 4 to Form T-1
          filed with Registration Statement No. 33-31019.)

     6.   The consent of the Trustee required by Section 321(b) of the Act.
          (Exhibit 6 to Form T-1 filed with Registration Statement No. 33-
          44051.)

     7.   A copy of the latest report of condition of the Trustee published
          pursuant to law or to the requirements of its supervising or examining
          authority.

                                      -2-
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                                   SIGNATURE

     Pursuant to the requirements of the Act, the Trustee, The Bank of New York,
a corporation organized and existing under the laws of the State of New York,
has duly caused this statement of eligibility to be signed on its behalf by the
undersigned, thereunto duly authorized, all in The City of New York, and State
of New York, on the 4th day of April, 2000.


                                   THE BANK OF NEW YORK

                                   By: /s/ MING SHIANG
                                      -----------------------
                                      Name:  MING SHIANG
                                      Title: VICE PRESIDENT

                                      -3-
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                      Consolidated Report of Condition of

                             THE BANK OF NEW YORK

                   of One Wall Street, New York, N.Y. 10286
                    And Foreign and Domestic Subsidiaries,
a member of the Federal Reserve System, at the close of business December 31,
1999, published in accordance with a call made by the Federal Reserve Bank of
this District pursuant to the provisions of the Federal Reserve Act.

<TABLE>
<CAPTION>
                                                                                               Dollar Amounts
ASSETS                                                                                          In Thousands
<S>                                                                                            <C>
Cash and balances due from depository institutions:
   Noninterest-bearing balances and currency and coin.....................................        $3,247,576
   Interest-bearing balances..............................................................         6,207,543
Securities:
   Held-to-maturity securities............................................................           827,248
   Available-for-sale securities..........................................................         5,092,464
Federal funds sold and Securities purchased under agreements to resell....................         5,306,926
Loans and lease financing receivables:
   Loans and leases, net of unearned income...............................................        37,734,000
   LESS: Allowance for loan and lease losses..............................................           575,224
   LESS: Allocated transfer risk reserve..................................................            13,278
   Loans and leases, net of unearned income, allowance, and reserve.......................        37,145,498
Trading Assets............................................................................         8,573,870
Premises and fixed assets (including capitalized leases)..................................           723,214
Other real estate owned...................................................................            10,962
Investments in unconsolidated subsidiaries and associated companies.......................           215,006
Customers' liability to this bank on acceptances outstanding..............................           682,590
Intangible assets.........................................................................         1,219,736
Other assets..............................................................................         2,542,157
                                                                                                 -----------
Total assets..............................................................................       $71,794,790
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</TABLE>
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<TABLE>
<CAPTION>
<S>                                                                                              <C>
LIABILITIES
Deposits:
   In domestic offices........................................................................   $27,551,017
   Noninterest-bearing........................................................................    11,354,172
   Interest-bearing...........................................................................    16,196,845
   In foreign offices, Edge and Agreement subsidiaries, and IBFs..............................    27,950,004
   Noninterest-bearing........................................................................       639,410
   Interest-bearing...........................................................................    27,310,594
Federal funds purchased and Securities sold under agreements to repurchase....................     1,349,708
Demand notes issued to the U.S.Treasury.......................................................       300,000
Trading liabilities...........................................................................     2,339,554
Other borrowed money:
   With remaining maturity of one year or less................................................       638,106
   With remaining maturity of more than one year through three years..........................           449
   With remaining maturity of more than three years...........................................        31,080
Bank's liability on acceptances executed and outstanding......................................       684,185
Subordinated notes and debentures.............................................................     1,552,000
Other liabilities.............................................................................     3,704,252
                                                                                                 -----------
Total liabilities.............................................................................    66,100,355
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EQUITY CAPITAL
Common stock..................................................................................     1,135,284
Surplus.......................................................................................       866,947
Undivided profits and capital reserves........................................................     3,765,900
Net unrealized holding gains (losses) on available-for-sale securities........................       (44,599)
Cumulative foreign currency translation adjustments...........................................       (29,097)
                                                                                                 -----------
Total equity capital..........................................................................     5,694,435
                                                                                                 -----------
Total liabilities and equity capital..........................................................   $71,794,790
                                                                                                 ===========
</TABLE>
<PAGE>

         I, Thomas J. Mastro, Senior Vice President and Comptroller of the
above-named bank do hereby declare that this Report of Condition has been
prepared in conformance with the instructions issued by the Board of Governors
of the Federal Reserve System and is true to the best of my knowledge and
belief.

                                                                Thomas J. Mastro

         We, the undersigned directors, attest to the correctness of this Report
of Condition and declare that it has been examined by us and to the best of our
knowledge and belief has been prepared in conformance with the instructions
issued by the Board of Governors of the Federal Reserve System and is true and
correct.

Thomas A. Renyi
Alan R. Griffith                Directors
Gerald L. Hassell

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