FIRST AMENDMENT TO REVOLVING CREDIT AGREEMENT

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                                                                   EXHIBIT 10.1


                               FIRST AMENDMENT TO
                           REVOLVING CREDIT AGREEMENT


                  THIS FIRST AMENDMENT TO REVOLVING CREDIT AGREEMENT (this
"Amendment") dated effective March 29, 2006, is entered into by and among
NORTHERN BORDER PIPELINE COMPANY, a Texas general partnership (the "Borrower"),
the several banks and other financial institutions and lenders from time to
time party hereto (the "Lenders"), WACHOVIA BANK, NATIONAL ASSOCIATION, in its
capacity as administrative agent for the Lenders (the "Administrative Agent"),
as issuing bank (the "Issuing Bank") and as swingline lender (the "Swingline
Lender"), SUNTRUST BANK, as syndication agent (the "Syndication Agent"), and
HARRIS NESBIT FINANCING, INC., BARCLAYS BANK PLC, and CITIBANK, N.A., as
co-documentation agents (the "Co-Documentation Agents"). All capitalized terms
used in this Amendment and not otherwise defined herein have the meanings
ascribed to such terms in the Credit Agreement (as defined below).

                             PRELIMINARY STATEMENT

                  The Borrower, the Administrative Agent, the Issuing Bank, the
Swingline Lender, the Syndication Agent, the Co-Documentation Agents, and the
Lenders are parties to that certain Revolving Credit Agreement dated as of May
16, 2005 (the "Credit Agreement").

                  The Borrower has requested that the Lenders amend the Credit
Agreement as set forth herein. The Lenders are agreeable to such request, upon
the conditions set forth herein.

                  NOW THEREFORE, in consideration of the premises and other
good and valuable consideration, the receipt and adequacy of which are hereby
acknowledged by the parties hereto, the Borrower, the Guarantor, the
Administrative Agent, the Issuing Bank, the Swingline Lender, the Syndication
Agent, the Co-Documentation Agents and the Lenders hereby agree as follows:

Section 1.         Amendments to Credit Agreement.

                  (a) Section 1.1 of the Credit Agreement is hereby amended by
replacing the definition of "Change in Control" in its entirety with the
following definition:

                           "Change in Control" shall mean (i) the failure of
                           Northern Border Partners to own, directly or
                           indirectly through one or more of its wholly owned
                           Subsidiaries, free and clear of all Liens, at least
                           50% of the partnership interests in Borrower, or
                           (ii) the failure of ONEOK, Inc. to own, directly or
                           indirectly, free and clear of all Liens, general
                           partner interests in Northern Border Partners and
                           the Intermediate Partnership such that the aggregate
                           voting rights of ONEOK, Inc. are greater than 50% of
                           the outstanding voting rights of all general
                           partners of Northern Border Partners and the
                           Intermediate Partnership.

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(b) Section 1.1 of the Credit Agreement is hereby further amended by replacing
the definition of "Northern Border Partners Credit Agreement" in its entirety
with the following definition:

                           "Northern Border Partners Credit Agreement" shall
                           mean that certain Amended and Restated Revolving
                           Credit Agreement, dated as of March 30, 2006, by
                           and among Northern Border Partners, the lenders from
                           time to time parties thereto, and SunTrust Bank, as
                           administrative agent, as amended, supplemented
                           restated or otherwise modified from time to time.

                  Section 2. No Obligation. Notwithstanding this Amendment, the
Lenders shall have no further obligation to modify the Credit Agreement as
amended by this Amendment and no further obligation of any kind shall be
inferred from this Amendment.

                  Section 3. Ratification. The Borrower hereby ratifies each of
its obligations under the Credit Agreement and the other Loan Documents to
which it is a party, and agrees and acknowledges that the Credit Agreement and
each of the other Loan Documents shall continue in full force and effect as
amended and modified by this Amendment. Nothing in this Amendment extinguishes,
novates or releases any right, claim, lien, security interest or entitlement of
any of the Lenders created by or contained in any of such documents, nor is the
Borrower released from any covenant, warranty or obligation created by or
contained therein except as expressly provided herein.

                  Section 4. Representations True; No Default. The Borrower
represents and warrants to the Administrative Agent and the Lenders that:

                  (a) this Amendment has been duly authorized, executed and
delivered on behalf of the Borrower. The Credit Agr