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                                                                    EXHIBIT 10.4

                                                                  EXECUTION COPY

                               SECURITY AGREEMENT

                            Dated as of June 6, 2003

                                      Among

                          THE WILLIAMS COMPANIES, INC.

                                   as Grantor

                                 CITIBANK, N.A.

                               as Collateral Agent

                                       and

                                 CITIBANK, N.A.

                           as Securities Intermediary

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                        T A B L E  O F  C O N T E N T S

<TABLE>
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SECTION                                                                                                PAGE
<S>                                                                                                    <C>
Section 1.   Grant of Security.................................................................          2

Section 2.   Security for Obligations..........................................................          2

Section 3.   The Collateral Account............................................................          3

Section 4.   Maintaining the Collateral........................................................          4

Section 5.   Investing of Amounts in the Collateral Account....................................          4

Section 6.   Release of Amounts................................................................          5

Section 7.   Representations and Warranties....................................................          5

Section 8.   Further Assurances................................................................          6

Section 9.   Post-Closing Changes..............................................................          7

Section 10.  Other Liens.......................................................................          7

Section 11.  Collateral Agent Appointed Attorney-in-Fact.......................................          7

Section 12.  The Collateral Agent's Duties.....................................................          7

Section 13.  Remedies..........................................................................          8

Section 14.  Indemnity and Expenses............................................................          8

Section 15.  Amendments; Waivers...............................................................          9

Section 16.  Notices, Etc......................................................................          9

Section 17.  Continuing Security Interest; Assignments under the Credit Agreement..............          9

Section 18.  Termination.......................................................................         10

Section 19.  Execution in Counterparts.........................................................         10

Section 20.  Governing Law.....................................................................         10
</TABLE>

Schedules I      -   Chief Executive Office, Type Of Organization, Jurisdiction
                     Of Organization And Organizational Identification Number

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                               SECURITY AGREEMENT

                  SECURITY AGREEMENT dated as of June 6, 2003 (as may be
amended, modified, supplemented, renewed, extended or restated from time to
time, this "AGREEMENT") among THE WILLIAMS COMPANIES, INC., a Delaware
corporation (the "GRANTOR"), CITIBANK, N.A., as collateral agent (in such
capacity, together with any successor collateral agent appointed pursuant to
Article VII of the Credit Agreement (as hereinafter defined), the "COLLATERAL
AGENT") for the Banks, the Issuing Banks, the Agent (each as defined in the
Credit Agreement) and the Collateral Agent (the "SECURED PARTIES") and CITIBANK,
N.A., as securities intermediary of Grantor (in such capacity, the "SECURITIES
INTERMEDIARY").

PRELIMINARY STATEMENTS.

                  (1)      The Grantor, Transcontinental Gas Pipe Line
Corporation and Northwest Pipeline Corporation have entered into a Credit
Agreement dated as of June 6, 2003 (said Agreement, as it may hereafter be
amended, amended and restated, supplemented or otherwise modified from time to
time, being the "CREDIT AGREEMENT") with the Secured Parties.

                  (2)      Pursuant to the Credit Agreement, the Grantor is
entering into this Agreement in order to grant to the Collateral Agent for the
ratable benefit of the Secured Parties a security interest (the "SECURITY
INTEREST") in the Collateral (as hereinafter defined) to secure the Secured
Obligations (as hereinafter defined).

                  (3)      The Grantor has opened Account No. 795241 (the
"COLLATERAL ACCOUNT"), with the Securities Intermediary at its office at 111
Wall Street, 14th Floor, New York, NY 10005, in the name of the Grantor but
under the control (within the meaning of Section 8-106 of the UCC (as defined
below)) of the Collateral Agent and subject to the terms of this Agreement.

                  (4)      The Securities Intermediary has agreed to calculate,
on a daily basis, the mark-to-market value of the securities held in the
Collateral Account and to provide such calculations to any Secured Party, as
such Secured Party may reasonably request from time to time.

                  (5)      It is a condition precedent to the making of
Revolving Credit Advances by the Banks and the issuance of Letters of Credit by
the Issuing Banks under the Credit Agreement that the Grantor shall have granted
the assignment and security interest and made the pledge and assignment
contemplated by this Agreement.

                  (6)      The Grantor will derive substantial direct and
indirect benefit from the transactions contemplated herein and by the other
Credit Documents.

                  (7)      Terms defined in the Credit Agreement and not
otherwise defined in this Agreement are used in this Agreement as defined in the
Credit Agreement. Further, unless otherwise defined in this Agreement or in the
Credit Agreement, terms defined in Article 8 or 9 of the UCC (as defined below)
and/or in the Federal Book Entry Regulations (as defined below) are used in this
Agreement as such terms are defined in such Article 8 or 9 and/or the Federal
Book Entry Regulations. "UCC" means the Uniform Commercial Code as in effect,
from time

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to time, in the State of New York; provided that, if perfection or the effect of
perfection or non-perfection or the priority of any security interest in any
Collateral is governed by the Uniform Commercial Code as in effect in a
jurisdiction other than the State of New York, "UCC" means the Uniform
Commercial Code as in effect from time to time in such other jurisdiction for
purposes of the provisions hereof relating to such perfection, effect of
perfection or non-perfection or priority. The term "FEDERAL BOOK ENTRY
REGULATIONS" means (a) the federal regulations contained in Subpart B
("Treasury/Reserve Automated Debt Entry System (TRADES)") governing book-entry
securities consisting of U.S. Treasury bonds, notes and bills and Subpart D
("ADDITIONAL PROVISIONS") of 31 C.F.R. Part 357, 31 C.F.R. Section 357.2,
Section 357.10 through Section 357.14 and Section 357.41 through Section 357.44
and (b) to the extent substantially identical to the federal regulations
referred to in clause (a) above (as in effect from time to time), the federal
regulations governing other book-entry securities.

                  NOW, THEREFORE, in consideration of the premises and in order
to induce the Banks to make Revolving Advances and the Issuing Banks to issue
Letters of Credit under the Credit Agreement, the Grantor hereby agrees with the
Collateral Agent for the ratable benefit of the Secured Parties as follows:

                  Section 1. Grant of Security. The Grantor hereby grants to the
Collateral Agent, for the ratable benefit of the Secured Parties, a security
interest in the Grantor's right, title and interest in and to the following
(collectively, the "COLLATERAL"):

                  (a) the Collateral Account and all funds and financial assets
         from time to time credited thereto (including, without limitation,
         Government Securities (as hereinafter defined)), all interest,
         dividends, distributions, cash, instruments and other property from
         time to time received, receivable or otherwise distributed in respect
         of or in exchange for any or all of such funds and financial assets,
         and all certificates and instruments, if any, from time to time
         representing or evidencing the Collateral Account;

                  (b) all interest, dividends, distributions, cash, instruments
         and other property from time to time received, receivable or otherwise
         distributed in respect of or in exchange for any or all of the then
         existing Collateral.

                  "GOVERNMENT SECURITIES" means any of the following and each
having a maturity of not greater than 2 years from the date of acquisition
thereof: (i) United States treasury securities, including bills, notes and
bonds; and (ii) securities of any agency of the Government of the United States
that are explicitly guaranteed by the full faith and credit of the Government of
the United States.

                  Section 2. Security for Obligations. This Agreement secures
the payment of all obligations of the Grantor and the Borrowers, now or
hereafter existing under the Credit Documents, whether direct or indirect,
absolute or contingent, and whether for principal, reimbursement obligations,
interest, fees, premiums, penalties, indemnifications, contract causes of
action, costs, expenses or otherwise (all such obligations being the "SECURED
OBLIGATIONS"). Without limiting the generality of the foregoing, this Agreement
secures, as to each Borrower, the payment of all amounts that constitute part of
the Secured Obligations and would be owed by such Borrower to any Secured Party
under the Credit Documents but for the fact that they are

<PAGE>

unenforceable or not allowable due to the existence of a bankruptcy,
reorganization or similar proceeding involving a Borrower.

                  Section 3. The Collateral Account. The Securities Intermediary
represents to and agrees with the Grantor and the Collateral Agent that:

                  (a) The Securities Intermediary maintains the Collateral
         Account in the name of, and for the benefit of, the Grantor, and all
         property held by the Securities Intermediary for the account of the
         Grantor is, and will continue to be, credited to the Collateral Account
         and maintained therein from time to time.

                  (b) The Collateral Account is a "securities account" as such
         term is used in Section 8-501(a) of the UCC and, in accordance
         therewith, (i) the Securities Intermediary is the securities
         intermediary with respect to the property credited from time to time to
         the Collateral Account, (ii) the Grantor is the entitlement holder with
         respect to the property credited from time to time to the Collateral
         Account and (iii) the Securities Intermediary agrees to treat the
         Grantor as entitled to exercise the rights that comprise the financial
         assets credited to the Collateral Account.

                  (c) The Securities Intermediary will comply with all
         notifications it receives directing it to invest, withdraw, transfer or
         redeem any property in the Collateral Account (each, an "ENTITLEMENT
         ORDER") originated by the Collateral Agent without further consent by
         the Grantor or any other person; provided that, without limiting the
         absolute obligation of the Securities Intermediary to comply with any
         Entitlement Order originated by the Collateral Agent, the Collateral
         Agent agrees with the Grantor that the Collateral Agent will not
         originate any Entitlement Order except in accordance with the terms of
         this Agreement; provided, further, that promptly thereafter, the
         Securities Intermediary shall give the Grantor written notice of the
         same at its address specified in the Credit Agreement.

                  (d) The Securities Intermediary shall comply with Entitlement
         Orders originated by the Grantor (subject to the terms of this
         Agreement); provided, however, if the Securities Intermediary receives
         a notice from the Collateral Agent that it will exercise exclusive
         control over the Collateral Account upon a Specified Event of Default
         (as hereinafter defined), the Securities Intermediary shall cease
         complying with Entitlement Orders or other directions concerning the
         Collateral Account, originated by the Grantor; provided, further, that
         in the event of any conflict between any Entitlement Order originated
         by the Grantor and any Entitlement Order originated by the Collateral
         Agent, the Entitlement Order originated by the Collateral Agent will
         prevail.

                  (e) The Securities Intermediary will treat all cash,
         securities and other property credited to the Collateral Account as
         "financial assets" as such term is defined in Section 8-102(a)(9) of
         the UCC.

                  (f) The State of New York is, and will continue to be, the
         Securities Intermediary's jurisdiction for purposes of Section
         8-110(e)(2) of the UCC so long as the Security Interest shall remain in
         effect.

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                  Section 4. Maintaining the Collateral. So long as any
Revolving Credit Advance or any other obligation of the Grantor or any Borrower
under any Credit Document shall remain unpaid, any Letter of Credit or Letter of
Credit Liability shall be outstanding or any Bank shall have any Commitment:

                  (a) The Grantor will maintain all Collateral only with the
         Collateral Agent or the Securities Intermediary (or such other Person
         acceptable to the Collateral Agent and the Grantor that complies with
         the provisions herein which has agreed, in a record authenticated by
         the Grantor, the Collateral Agent and such Person, to (i) comply with
         instructions originated by the Collateral Agent directing the
         disposition of funds in the Collateral Account without the further
         consent of the Grantor and (ii) waive or subordinate in favor of the
         Collateral Agent all claims of such Person (including, without
         limitation, claims by way of a security interest, lien or right of
         setoff or right of recoupment) to the Collateral, which authenticated
         record shall be in form and substance satisfactory to the Collateral
         Agent and the Grantor).

                  (b) The Collateral Agent shall, at the direction of the
         Grantor, at any time and without notice to, or consent from, any Bank,
         and notwithstanding the occurrence or continuance of any Event of
         Default, transfer, or direct the transfer of, funds from the Collateral
         Account to the Agent to satisfy any Borrower's Obligations under the
         Credit Agreement whether or not such Obligations are then due and
         payable.

                  (c) The Collateral Agent shall, at the request of the Agent,
         at any time and without consent from the Grantor or any Borrower,
         transfer, or direct the transfer of, funds from the Collateral Account
         to satisfy any Borrower's obligations under the Credit Documents which
         are then due and payable (provided that promptly thereafter the
         Collateral Agent shall give the Grantor written notice of the same) if
         an Event of Default shall have occurred and be continuing.

                  (d) Subject to Sections 4(b) and 6(d) hereof, upon the
         occurrence and continuance of an Event of Default under Section 6.1(d)
         or (f) of the Credit Agreement (each a "SPECIFIED EVENT OF DEFAULT"),
         the Collateral Agent shall have sole right to direct the investment and
         disposition of funds with respect to the Collateral Account and it
         shall be a term and condition of the Collateral Account,
         notwithstanding any term or condition to the contrary in any other
         agreement relating to the Collateral Account that no amount (including,
         without limitation, interest credited thereto) will be paid or released
         to or for the account of, or withdrawn by or for the account of, the
         Grantor, any Borrower or any other Person from the Collateral Account.

                  (e) Contemporaneously herewith, the Grantor shall cause a
         certificate of incumbency to be executed in the form of Exhibit A
         hereto (such certificate may be amended or modified by the Grantor from
         time to time by adding or deleting the names of persons authorized to
         act on behalf of the Grantor with respect to the Collateral Account).

                  Section 5. Investing of Amounts in the Collateral Account. So
long as no Specified Event of Default shall have occurred and be continuing and
subject to the provisions of

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Sections 4, 6 and 18 hereof, the Grantor will be permitted to (a) invest, or
direct the Securities Intermediary to invest, amounts received with respect to
the Collateral Account in Government Securities, and only Government Securities,
and credited to the Collateral Account, as the Grantor may select and (b) invest
interest paid on the Government Securities referred to in clause (a) above, and
reinvest other proceeds of any such Government Securities that may mature or be
sold, in each case in such Government Securities credited in the same manner.
Interest and proceeds that are not invested or reinvested in Government
Securities as provided above shall be deposited and held in the Collateral
Account (such uninvested amounts shall not earn or accrue interest thereon). In
addition, so long as no Specified Event of Default shall have occurred and be
continuing, the Grantor shall have the right at any time to exchange, or direct
the Securities Intermediary to exchange, such Government Securities for similar
Government Securities of smaller or larger determinations, or for other
Government Securities, credited to the Collateral Account.

                  Section 6. Release of Amounts. So long as (x) no Specified
Event of Default shall have occurred and be continuing, and (y) the
mark-to-market value of the Collateral shall exceed the Collateral Coverage
Requirement (i) by not less than $1,000,000 at any time, and upon two Business
Days prior written notice by the Grantor to the Collateral Agent, or (ii) on the
last Business Day of each month, if requested by the Grantor, then the
Collateral Agent shall immediately transfer, or direct the Securities
Intermediary to transfer, such excess amount, or a portion thereof as may be
requested by the Grantor, to the Grantor or at its order.

                  (a) So long as (x) no Specified Event of Default shall have
occurred and be continuing, and (y) upon two Business Days prior written notice
by the Grantor to the Collateral Agent that (i) any outstanding Revolving Credit
Advance has been repaid or (ii) any outstanding Letter of Credit has expired and
is undrawn, then the Collateral Agent shall immediately transfer, or direct the
Securities Intermediary to transfer, such amount in excess of the Collateral
Coverage Requirement, or a portion thereof as may be requested by the Grantor,
as is then on deposit in the Collateral Account to the Grantor or at its order.

                  (b) Upon the occurrence of a Mandatory Prepayment Event and
unless the Grantor has otherwise paid all then outstanding obligations of the
Grantor with respect to the Revolving Credit Advances, the Collateral Agent
shall, at the direction of the Agent, pay and release, or direct the Securities
Intermediary to pay and release, to the Agent to be applied to all then
outstanding obligations of the Grantor or any Borrower with respect to the
Revolving Credit Advances, such amount as is then on deposit in the Collateral
Account.

                  (c) Notwithstanding Sections 6(a) and 6(b), and whether or not
an Event of Default has occurred and is continuing, upon two Business Days prior
written notice by the Grantor to the Collateral Agent, the Collateral Agent
shall immediately transfer, or direct the Securities Intermediary to transfer,
such amount in excess of 107.5% of the Total Credit Exposure, or a portion
thereof as may be requested by the Grantor, as is then on deposit in the
Collateral Account to the Grantor or at its order.

                  Section 7. Representations and Warranties. The Grantor
represents and warrants as follows:

<PAGE>

                  (a) The Grantor's exact legal name, as defined in Section
         9-503(a) of the UCC, is correctly set forth in Schedule 1 hereto. The
         Grantor is located (within the meaning of Section 9-307 of the UCC) and
         has its chief executive office in the state or jurisdiction set forth
         in Schedule I hereto. The information set forth in Schedule I hereto
         with respect to the Grantor is true and accurate in all respects. The
         Grantor has not previously changed its name, location, chief executive
         office, type of organization, jurisdiction of organization or
         organizational identification number from those set forth in Schedule I
         within the previous five years of the date hereof.

                  (b) The Grantor is the legal and beneficial owner of the
         Collateral free and clear of any lien, claim, option or right of
         others, except for the security interest created under this Agreement.
         No effective financing statement or other instrument similar in effect
         covering all or any part of such Collateral or listing the Grantor or
         any trade name of the Grantor as debtor is on file in any recording
         office, except such as may have been filed in favor of the Collateral
         Agent relating to the Credit Documents.

                  (c) All filings and other actions necessary to perfect the
         security interest in the Collateral of the Grantor created under this
         Agreement have been duly made or taken and are in full force and
         effect, and this Agreement creates in favor of the Collateral Agent for
         the benefit of the Secured Parties a valid and, together with such
         filings and other actions, perfected first priority security interest
         in the Collateral of the Grantor, securing the payment of the Secured
         Obligations.

                  (d) No authorization or approval or other action by, and no
         notice to or filing with, any governmental authority or regulatory body
         or any other third party is required for (i) the grant by the Grantor
         of the security interest granted hereunder or for the execution,
         delivery or performance of this Agreement by the Grantor, or (ii) the
         perfection or maintenance of the security interest created hereunder
         (including the first priority nature of such security interest), except
         for the filing of financing and continuation statements under the UCC,
         which financing statements have been duly filed and are in full force
         and effect.

                  (e) The aggregate mark-to-market value of all Collateral in
         the Collateral Account for which the Collateral Agent has a
         first-priority perfected security interest is equal to or greater than
         the Collateral Coverage Requirement as of the date hereof.

                  Section 8. Further Assurances. The Grantor agrees that from
time to time, at the expense of the Grantor, it will promptly execute and
deliver, or otherwise authenticate, all further instruments and documents, and
take all further action that may be necessary or desirable, or that the
Collateral Agent may reasonably request, in order to perfect and protect the
security interest granted or purported to be granted by the Grantor hereunder or
to enable the Collateral Agent to exercise and enforce its rights and remedies
hereunder with respect to the Collateral. Without limiting the generality of the
foregoing, the Grantor will promptly with respect to Collateral: (i) execute or
authenticate and file such financing or continuation statements, or amendments
thereto, and such other instruments or notices, as may be necessary or
desirable, or as the Collateral Agent may reasonably request, in order to
perfect and preserve the security interest granted or purported to be granted by
the Grantor hereunder; and (ii) deliver to the Collateral

<PAGE>

Agent evidence that all other action that the Collateral Agent may deem
reasonably necessary or desirable in order to perfect and protect the security
interest created by the Grantor under this Agreement has been taken.

                  (a) The Grantor hereby authorizes the Collateral Agent to file
one or more financing or continuation statements, and amendments thereto,
including, without limitation, one or more financing statements indicating that
such financing statements cover the Collateral (or words of similar effect) of
the Grantor, in each case without the signature of the Grantor. A photocopy or
other reproduction of this Agreement or any financing statement covering the
Collateral or any part thereof shall be sufficient as a financing statement
where permitted by law. The Grantor ratifies its authorization for the
Collateral Agent to have filed such financing statements, continuation
statements or amendments filed prior to the date hereof.

                  (b) The Grantor will furnish to the Collateral Agent from time
to time statements and schedules further identifying and describing the
Collateral and such other reports in connection with such Collateral as the
Collateral Agent may reasonably request in writing, all in reasonable detail.

                  Section 9. Post-Closing Changes. The Grantor will not change
its name, type of organization, jurisdiction of organization, organizational
identification number or location from those set forth in Section 7(a) of this
Agreement without first giving at least 15 Business Days' prior written notice
to the Collateral Agent and taking all action required by the Collateral Agent
for the purpose of perfecting or protecting the security interest granted by
this Agreement. If the Grantor does not have an organizational identification
number and later obtains one, it will forthwith notify the Collateral Agent of
such organizational identification number.

                  Section 10. Other Liens. The Grantor agrees that it will not
create or permit to suffer to exist any lien upon or with respect to any of the
Collateral except for the pledge, assignment and security interest created under
this Agreement.

                  Section 11. Collateral Agent Appointed Attorney-in-Fact. The
Grantor hereby irrevocably appoints the Collateral Agent the Grantor's
attorney-in-fact, with full authority in the place and stead of the Grantor and
in the name of the Grantor or otherwise, from time to time upon the occurrence
and during the continuance of an Event of Default, in the Collateral Agent's
discretion, to take any action and to execute any instrument that the Collateral
Agent may deem necessary to accomplish the purposes of this Agreement.

                  Section 12. The Collateral Agent's Duties. The powers
conferred on the Collateral Agent hereunder are solely to protect the Secured
Parties' interest in the Collateral and shall not impose any duty upon it to
exercise any such powers. Except for the safe custody of any Collateral in its
possession and the accounting for moneys actually received by it hereunder, the
Collateral Agent shall have no duty as to any Collateral, as to ascertaining or
taking action with respect to exchanges, maturities, tenders or other matters
relative to any Collateral, whether or not any Secured Party has or is deemed to
have knowledge of such matters. The Collateral Agent shall be deemed to have
exercised reasonable care in the custody and preservation of any Collateral in
its possession if such Collateral is accorded treatment substantially equal to
that which it accords its own property.

<PAGE>

                  Section 13. Remedies. If any Event of Default shall have
occurred and be continuing:

                  (a) The Collateral Agent may exercise in respect of the
         Collateral, in addition to other rights and remedies provided for
         herein or otherwise available to it, all the rights and remedies of a
         secured party upon default under the UCC (whether or not the UCC
         applies to the affected Collateral) and also may: (i) subject to
         Section 13(b), exercise any and all rights and remedies of the Grantor
         under or in connection with the Collateral, or otherwise in respect of
         the Collateral, including, without limitation, withdraw, or cause or
         direct the withdrawal, of all funds with respect to the Collateral and
         (ii) exercise all other rights and remedies with respect to the other
         Collateral, including, without limitation, those set forth in Section
         9-607 of the UCC.

                  (b) Any cash held by or on behalf of the Collateral Agent and
         all cash proceeds received by or on behalf of the Collateral Agent in
         respect of any collection from, or other realization upon all or any
         part of the Collateral shall be held by the Collateral Agent as
         collateral for, and/or then or at any time thereafter applied (after
         payment of any amounts payable to the Collateral Agent pursuant to
         Section 3 hereof) in whole or in part by the Collateral Agent for the
         ratable benefit of the Secured Parties against, all or any part of the
         Secured Obligations, in the following manner:

                           (i)      first, paid to the Collateral Agent, the
                  Securities Intermediary and the Agent for any amounts then
                  owing to the Collateral Agent, the Securities Intermediary and
                  the Agent pursuant to Section 8.4 of the Credit Agreement or
                  otherwise under the Credit Documents, ratably in accordance
                  with such respective amounts then owing to the Collateral
                  Agent, the Securities Intermediary and the Agent; and

                           (ii)     second, ratably paid to the Banks and the
                  Issuing Banks or any amounts then owing to them under the
                  Credit Documents ratably in accordance with such respective
                  amounts then owing to such Banks and Issuing Banks.

         Any surplus of such cash or cash proceeds held by or on the behalf of
         the Collateral Agent and remaining after payment in full of all the
         Secured Obligations shall be paid over to the Grantor or to whomsoever
         may be lawfully entitled to receive such surplus.

                  (c) The Collateral Agent may, without notice to the Grantor
         except as required by law and at any time or from time to time, charge,
         set-off and otherwise apply all or any part of the Secured Obligations
         against any funds held with respect to the Collateral.

                  Section 14. Indemnity and Expenses. The Grantor agrees to
indemnify, defend and save and hold harmless each Secured Party and the
Securities Intermediary and each of their affiliates and their respective
officers, directors, employees, agents and advisors (each, an "INDEMNIFIED
PARTY") from and against, and shall pay on demand, any and all claims, damages,
losses, liabilities and expenses (including, without limitation, reasonable fees
and expenses of counsel) that may be incurred by or asserted or awarded against
any Indemnified Party, in each case arising out of or in connection with or
resulting from this Agreement (including, without

<PAGE>

limitation, enforcement of this Agreement), except to the extent such claim,
damage, loss, liability or expense is found in a final, non-appealable judgment
by a court of competent jurisdiction to have resulted from such Indemnified
Party's gross negligence or willful misconduct or the gross negligence or
willful misconduct of such Indemnified Party's affiliates, officers, directors,
employees, agents or advisors.

                  (a) The Grantor will upon demand pay to the Collateral Agent
and the Securities Intermediary the amount of any and all reasonable expenses,
including, without limitation, the reasonable fees and expenses of its counsel,
that the Collateral Agent and the Securities Intermediary may incur in
connection with (i) the administration of this Agreement, (ii) the custody,
preservation, use or operation of, or the sale of, collection from or other
realization upon, any of the Collateral, (iii) the exercise or enforcement of
any of the rights of the Collateral Agent or the other Secured Parties hereunder
or (iv) the failure by the Grantor to perform or observe any of the provisions
hereof.

                  Section 15. Amendments; Waivers. No amendment or waiver of any
provision of this Agreement, and no consent to any departure by the Grantor
herefrom, shall in any event be effective unless the same shall be in writing
and signed by the Collateral Agent and the Securities Intermediary, and then
such waiver or consent shall be effective only in the specific instance and for
the specific purpose for which given. No failure on the part of the Collateral
Agent or any other Secured Party or the Securities Intermediary to exercise, and
no delay in exercising any right hereunder, shall operate as a waiver thereof;
nor shall any single or partial exercise of any such right preclude any other or
further exercise thereof or the exercise of any other right.

                  Section 16. Notices, Etc. All notices and other communications
provided for hereunder shall be either (i) in writing (including telegraphic,
telecopier or telex communication) and mailed, telegraphed, telecopied, telexed
or otherwise delivered or (ii) by electronic mail (if electronic mail addresses
are designated as provided below) confirmed immediately in writing, in the case
of the Borrowers or the Collateral Agent, addressed to it at its address
specified in the Credit Agreement, if to the Securities Intermediary, at its
address specified on its signature page hereto or, as to any party, at such
other address as shall be designated by such party in a written notice to the
other parties. All such notices and other communications shall, when mailed,
telegraphed, telecopied, telexed, sent by electronic mail or otherwise, be
effective when deposited in the mails, delivered to the telegraph company,
telecopied, confirmed by telex answerback, sent by electronic mail and confirmed
in writing, or otherwise delivered (or confirmed by a signed receipt),
respectively, addressed as aforesaid; except that notices and other
communications to the Collateral Agent or the Securities Intermediary shall not
be effective until received by the Collateral Agent or the Securities
Intermediary, as the case may be. Delivery by telecopier of an executed
counterpart of any amendment or waiver of any provision of this Agreement or
Schedule hereto shall be effective as delivery of an original executed
counterpart thereof.

                  Section 17. Continuing Security Interest; Assignments under
the Credit Agreement. This Agreement shall create a continuing security interest
in the Collateral and shall (a) remain in full force and effect until the latest
of (i) the payment in full in cash of the Secured Obligations, (ii) the
Termination Date and (iii) the termination or expiration of all Letters of

<PAGE>

Credit, (b) be binding upon the Grantor, its successors and assigns and (c)
inure, together with the rights and remedies of the Collateral Agent hereunder,
to the benefit of the Secured Parties and their respective successors,
transferees and assigns. Without limiting the generality of the foregoing clause
(c), any Bank may assign or otherwise transfer all or any portion of its rights
and obligations under the Credit Agreement in accordance therewith (including,
without limitation, all or any portion of its Commitments, the Revolving Credit
Advances owing to it and the Note or Notes, if any, held by it) to any other
Person, and such other Person shall thereupon become vested with all the
benefits in respect thereof granted to such Bank herein or otherwise, in each
case as provided in Section 8.6 of the Credit Agreement.

                  Section 18. Termination. Upon the latest of (i) the payment in
full in cash of the Secured Obligations, (ii) the Termination Date and (iii) the
termination or expiration of all Letters of Credit, the security interest
granted hereby shall terminate and all rights to the Collateral shall revert to
the applicable Grantor. Upon any such termination, the Collateral Agent will, at
the Grantor's expense, execute and deliver to the Grantor such documents as the
Grantor shall reasonably request to evidence such termination.

                  Section 19. Execution in Counterparts. This Agreement may be
executed in any number of counterparts, each of which when so executed shall be
deemed to be an original and all of which taken together shall constitute one
and the same agreement. Delivery of an executed counterpart of a signature page
to this Agreement by telecopier shall be effective as delivery of an original
executed counterpart of this Agreement.

                  Section 20. Governing Law. This Agreement shall be governed
by, and construed in accordance with, the laws of the State of New York.

                              [Signatures follow.]

<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
     executed by their respective officers thereunto duly authorized, as of the
     date first above written.

                                THE WILLIAMS COMPANIES, INC., as Grantor

                                By: /s/  Steven J. Malcolm
                                Name:  Steven J. Malcolm
                                Title: Chairman of the Board

                                CITIBANK, N.A., as Collateral Agent and Secured
                                Party

                                By: /s/  Gordon H. DeKuyper
                                Name:  Gordon H. DeKuyper
                                Title: Vice President

                                CITIBANK, N.A., as Securities Intermediary
                                By: /s/ Camille Tomao
                                Name: Camille Tomao
                                Title: Vice President

                                Address:
                                       111 Wall Street, 14th Floor
                                       New York, New York  10055

<PAGE>

                                                               SCHEDULE I TO THE
                                                              SECURITY AGREEMENT

          CHIEF EXECUTIVE OFFICE, TYPE OF ORGANIZATION, JURISDICTION OF
              ORGANIZATION AND ORGANIZATIONAL IDENTIFICATION NUMBER

<TABLE>
<CAPTION>
                    CHIEF EXECUTIVE           TYPE OF         JURISDICTION OF   ORGANIZATIONAL
   GRANTOR              OFFICE              ORGANIZATION        ORGANIZATION       I.D. NO.
---------------   -------------------       ------------      ---------------   --------------
<S>               <C>                       <C>               <C>               <C>
The Williams      One Williams Center
Companies, Inc.   Tulsa, OK  74172          Corporation           Delaware          2116534
</TABLE>

<PAGE>

                                                                EXHIBIT A TO THE
                                                              SECURITY AGREEMENT

                            CERTIFICATE OF INCUMBENCY

                  Reference is made to (i) the credit agreement, dated as of
June 6, 2003 (as may be further amended, modified, supplemented, renewed,
extended or restated from time to time, the "CREDIT AGREEMENT"), by and among
The Williams Companies, Inc. (the "COMPANY"), Northwest Pipeline Corporation,
Transcontinental Gas Pipe Line Corporation, each a Delaware corporation, as
borrowers, the banks, issuing banks, financial institutions and other
institutional lenders party thereto, and Citibank, N.A., as agent and collateral
agent ("CITIBANK"), and (ii) the security agreement, dated as of June 6, 2003
(the "SECURITY AGREEMENT"), made by the Company to Citibank.

                  The undersigned certifies that s/he is the [INSERT TITLE] of
the Company, and as such s/he is authorized to execute this certificate and
further certifies that the following persons have been elected or appointed, are
qualified, and are now acting in the capacity or capacities indicated below, and
that the signatures set forth opposite their respective names are their true and
genuine signatures. S/he further certifies that any of the persons listed below
is authorized [CHOOSE ONE: INDIVIDUALLY OR JOINTLY WITH ONE OTHER PERSON] to
execute agreements and give written instructions with regard to any matters
pertaining to the Collateral Account (as defined in the Security Agreement);
provided, that, in all respects, such execution of agreements and giving of
written instructions shall be subject to the provisions of the Credit Agreement
and the Security Agreement:

<TABLE>
<CAPTION>
             Name                                Title / Phone                                Signature
             ----                                -------------                                ----------
<S>                                  <C>                                          <C>
                                                        /
_______________________________      _______________________________________      ___________________________________
                                                       /
_______________________________      _______________________________________      ___________________________________
                                                       /
_______________________________      _______________________________________      ___________________________________
</TABLE>

                  IN WITNESS WHEREOF, I have caused this certificate to be duly
executed and delivered as of the ___ day of ______, 200__.

                                                THE WILLIAMS COMPANIES, INC.

                                                [TO BE SIGNED BY AN OFFICER
                                                OTHER THAN ONE LISTED ABOVE]

                                                By __________________________
                                                   Name:
                                                   Title: