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FOURTH AMENDING AGREEMENT  (Syndicated Term Credit Facility)
   POTASH CORPORATION OF SASKATCHEWAN INC. Borrower
   THE FINANCIAL INSTITUTIONS SET FORTH ON THE SIGNATURE PAGES HEREOF
UNDER THE HEADING LENDERS: Lenders Lender
   THE BANK OF NOVA SCOTIA, Agent
    1. Interpretation
  Agreement
 Credit Agreement




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- 2 -     2. Amendments and Supplements
 Amendment to Definition of Maturity Date
 Maturity Date
 Reporting Requirements of Material Subsidiaries
 Increase in Control of Borrower Threshold
 3. Amendment Fee
  4. Representations and Warranties




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- 3 - (a)
    
    Capacity, Power and Authority
 (i)
    
    It is duly incorporated and is validly subsisting under the
laws of its jurisdiction of incorporation and has all the requisite corporate
capacity, power and authority to carry on its business as presently conducted
and to own its property; and
 (ii)
    
    It has the requisite corporate capacity, power and authority to
execute and deliver this Agreement.
 (b)
    
    Authorization; EnforceabilityIt has taken or caused to be taken all necessary action to authorize, and has duly
executed and delivered, this Agreement, and this Agreement is a legal, valid and
binding obligation of it enforceable against it in accordance with its terms,
subject to applicable bankruptcy, reorganization, winding up, insolvency, moratorium
or other laws of general application affecting the enforcement of creditors rights
generally and to the equitable and statutory powers of the courts having
jurisdiction with respect thereto.
 (c)
    
    Compliance with Other InstrumentsThe execution, delivery and performance by the Borrower of this Agreement and the
consummation of the transactions contemplated herein do not conflict with, result in
any breach or violation of, or constitute a default under the terms, conditions or
provisions of its articles, by-laws or other constating documents or any unanimous
shareholder agreement relating to, the Borrower or of any law, regulation, judgment,
decree or order binding on or applicable to the Borrower or to which its property is
subject or of any material agreement, lease, licence, permit or other instrument to
which the Borrower or any of its Subsidiaries is a party or is otherwise bound or by
which any of them benefits or to which any of their property is subject and do not
require the consent or approval of any Official Body or any other party.
  5. Condition Precedent




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- 4 -  6. Confirmation of Credit Agreement and other Loan Documents
  7. Further Assurances
  8. Enurement
  [the remainder of this page has intentionally been left blank]




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- 5 - 9. Counterparts
   POTASH CORPORATION OF SASKATCHEWAN INC.By:
    /s/ Wayne BrownleeName:
    Wayne R. BrownleeTitle:
    Executive Vice President, Treasurer and Chief
Financial OfficerBy:
    /s/ Denis SiroisName:
    Denis A. SiroisTitle:
    Vice President & Corporate Controller LENDERS:THE BANK OF NOVA SCOTIABy:
    /s/ Jeff T. CebrykName:
    Jeff T. CebrykTitle:
    Director




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- 6 -  ROYAL BANK OF CANADABy:
    /s/ Michael ManionName:
    Michael ManionTitle:
    Authorized SignatoryBy:Name:Title: CREDIT SUISSE, TORONTO BRANCHBy:
    /s/ Alain DaoustName:
    Alain DaoustTitle:
    DirectorBy:
    /s/ Bruce WetherlyName:
    Bruce F. WetherlyTitle:
    Director BANK OF AMERICA, N.A.,
CANADA BRANCHBy:
    /s/ Medina Sales de AndradeName:
    Medina Sales de AndradeTitle:
    Assistant Vice PresidentBy:Name:Title: COMERICA BANKBy:
    /s/ Nick ChristopoulosName:
    Nick ChristopoulosTitle:
    Vice PresidentBy:Name:Title:




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- 7 - BANK OF MONTREALBy:
    /s/ R. WrightName:
    R. WrightTitle:
    DirectorBy:Name:Title: BANK OF TOKYO-MITSUBISHI UFJ (CANADA)By:
    /s/Name:Title:By:Name:Title: BNP PARIBAS (CANADA)By:
    /s/ Allan FordyceName:
    Allan FordyceTitle:
    DirectorBy:
    /s/ Edward PakName:
    Edward PakTitle:
    Vice President HSBC BANK CANADABy:
    /s/ Sarah YeeName:
    Sarah YeeTitle:
    Relationship ManagerBy:
    /s/ Quyen QuachName:
    Quyen QuachTitle:
    Analyst




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- 8 -  RABOBANK NEDERLAND,
CANADIAN BRANCHBy:
    /s/ Rommel J. DomingoName:
    Rommel J. DomingoTitle:
    Vice PresidentBy:
    /s/ Anthony H. LiangName:
    Anthony H. LiangTitle:
    Executive Director SOCIÉTÉ GÉNÉRALE (CANADA BRANCH)By:
    /s/ Roxana F. PateanuName:
    Roxana F. PateanuTitle:
    Vice-President Corporate Credit GroupBy:
    /s/ Yvon J. Jeghers, CAName:
    Yvon J. Jeghers, CATitle:
    Managing Director AGENT:THE BANK OF NOVA SCOTIA,in its capacity as AgentBy:
    /s/ Jeff T. CebrykName:
    Jeff T. CebrykTitle:
    Director