-2-“**Agreement**” means this agreement, as amended, modified, supplemented or restated from time to time.“**Credit Agreement**” means the credit agreement made as of May 29, 2008 between the Borrower, TheBank of Nova Scotia, Royal Bank of Canada and Bank of Montreal and such other financialinstitutions as become party thereto, as lenders, and the Agent.1.2.     Capitalized terms used herein without express definition shall have the same meanings hereinas are ascribed thereto in the Credit Agreement.1.3.     The division of this Agreement into Sections and the insertion of headings are for convenienceof reference only and shall not affect the construction or interpretation of this Agreement. Theterms “this Agreement”, “hereof”, “hereunder” and similar expressions refer to this Agreement andnot to any particular Section or other portion hereof and include any agreements supplementalhereto.1.4.     This Agreement shall be governed by and construed in accordance with the laws of the Provinceof Ontario and the federal laws of Canada applicable therein.**2.**     **Amendments and Supplements**2.1.     ***Increase in Credit Facility.***The existing definition of “Credit Facility” contained inSection 1.1 of the Credit Agreement is hereby amended to delete “U.S.$750,000,000” where it appearsin the first line thereof and to substitute therefor the amount of “U.S.$1,000,000,000”. Theparties hereto hereby confirm and agree that the maximum principal amount of the Credit Facility ishereby increased to U.S.$1,000,000,000 from U.S.$750,000,000.*2.2.*     ***Addition of New Lenders.*** (a) ***Addition of New Lenders.***The parties hereto hereby confirm and agree that,from and after the date hereof, each of the New Lenders shall be a Lender for allpurposes of the Credit Agreement and the other Documents having the Commitment setforth opposite its name on Schedule A hereto and all references herein or therein to“Lenders” or a “Lender” shall be deemed to include the New Lenders.  (b) ***Novation of New Lenders.***Each of the New Lenders hereby agrees that it will bebound by the Credit Agreement and the other Documents as a Lender to the extent of itsCommitment as fully as if it had been an original party to the Credit Agreement.  (c) ***The Agent.***Without in any way limiting the other provisions hereof, each ofthe New Lenders irrevocably appoints and authorizes the Agent to take such action asagent on its behalf and to exercise such powers under the Credit Agreement and theother Documents as are delegated to the Agent by the terms thereof, together with suchpowers as are reasonably incidental thereto, all in accordance with the provisions ofthe Credit Agreement.

 

-3- (d) ***Independent Credit Decision.***Each of the New Lenders and, with respect to theincrease in its Commitment, Royal Bank of Canada acknowledges to the Agent that suchNew Lender and Royal Bank of Canada has itself been, and will continue to be, solelyresponsible for making its own independent appraisal of and investigations into thefinancial condition, creditworthiness, condition, affairs, status and nature of theBorrower and its Subsidiaries, all of the matters and transactions contemplated hereinand in the Credit Agreement and other Documents and all other matters incidental to theCredit Agreement and the other Documents. Each of the New Lenders and Royal Bank ofCanada confirms with the Agent that it does not rely, and it will not hereafter rely,on the Agent: (i) to check or inquire on its behalf into the adequacy, accuracyor completeness of any information provided by the Borrower, its Subsidiariesor any other person under or in connection with the Credit Agreement and otherDocuments or the transactions therein contemplated (whether or not suchinformation has been or is hereafter distributed to it by the Agent); or  (ii) to assess or keep under review on its behalf the financialcondition, creditworthiness, condition, affairs, status or nature of theBorrower and its Subsidiaries.   Each of the New Lenders and Royal Bank of Canada acknowledges to the Agent that acopy of the Credit Agreement (including a copy of the Schedules annexed thereto) hasbeen made available to it for review and further acknowledges and agrees that it hasreceived copies of such other Documents and such other information that it hasrequested for the purposes of its investigation and analysis of all matters relatedto this Agreement, the Credit Agreement, the other Documents and the transactionscontemplated hereby and thereby. Each of the New Lenders and Royal Bank of Canadaacknowledges to the Agent that it is satisfied with the form and substance of theCredit Agreement (as amended and supplemented hereby) and the other Documents.  (e) ***Consent of Agent.***The Agent hereby consents to the addition of each of the NewLenders into the Credit Agreement as a Lender and agrees to recognize each of the NewLenders as a Lender under the Credit Agreement as fully as if each such New Lender hadbeen an original party to the Credit Agreement.2.3.     ***New Schedule A; Revised Commitments.***Schedule A to the Credit Agreement is hereby deleted inits entirety and replaced with Schedule A attached hereto, *inter alia*, to increase the Commitmentof Royal Bank of Canada to the amount set forth opposite its name on such new Schedule A.2.4.     ***Fees Payable in Respect of Increase in Commitments and in Respect of New Lender Commitments.***The Borrower hereby agrees to pay to the Agent, for Royal Bank of Canada, a fee in United StatesDollars in an amount equal to 0.10% of the increase in the Commitment of Royal Bank of Canada. Inaddition, the Borrower hereby agrees to pay to the Agent, for eachNew Lender, a fee in United States Dollars in an amount equal to 0.10% of the Commitment of eachNew Lender.

 

-4-**3.**     **Funding of Loans to Reflect Revised Commitments**3.1.     ***Funding of Outstanding Loans Under the Credit Facility.***In order to give effect to theforegoing, upon the satisfaction of the conditions precedent set forth below, the Lenders herebyagree to take all steps and actions and execute and deliver all agreements, instruments and otherdocuments as may be required by the Agent or any of the Lenders (including the assignment ofinterests in, or the purchase of participations in, existing Loans) to give effect to the foregoingincrease in the Credit Facility and revised Commitments and to ensure that the aggregateObligations owing to each Lender under the Credit Facility are outstanding in proportion to eachLender’s Rateable Portion of all outstanding Obligations under the Credit Facility after givingeffect to such increase and revised Commitments; provided that, the foregoing provisions of thisSection 3.1 shall not apply to Libor Loans, Bankers’ Acceptances and BA Equivalent Advancesoutstanding on the date hereof, such Libor Loans, Bankers’ Acceptances and BA Equivalent Advancesbeing subject to and dealt with pursuant to Sections 3.2 and 3.3 hereof, respectively.*3.2.*     ***Outstanding Libor Loans.*** (a) The parties hereby acknowledge that, on the date hereof, Libor Loans havingInterest Periods ending after the date hereof are outstanding (the “**Outstanding LiborLoans**”). Notwithstanding any provision of the Credit Agreement or this Agreement tothe contrary, until the expiry of the applicable Interest Periods, each of the NewLenders and the Lenders which are increasing their respective Commitments shall not(but in the case of the Lenders increasing their respective Commitments only withrespect to the increased amounts of their respective Commitments) have any right,title, benefit or interest in or to any Outstanding Libor Loans nor any obligation orliability to the other Lenders in respect thereof.  (b) From time to time, as the Interest Periods of the Outstanding Libor Loansexpire and Rollovers and Conversions are made by the Borrower in respect thereof, eachof the Lenders shall participate in the Loans effecting such Rollovers and Conversionsto the full extent of its revised Commitment after giving effect to the provisions ofthis Agreement.*3.3.*     ***Outstanding Bankers’ Acceptances.*** (a) The parties hereby acknowledge that, on the date hereof, Bankers’ Acceptancesand BA Equivalent Advances having terms to maturity ending after the date hereof may beoutstanding (the “**Outstanding BAs**”). Notwithstanding any provision of the CreditAgreement or this Agreement to the contrary, each of the New Lenders and the Lenderswhich are increasing their respective Commitments shall not (but in the case of theLenders increasing their respective Commitments only with respect to the increasedamounts of their respective Commitments) have any right, title, benefit or interest inor to any Outstanding BAs nor any obligation or liability to the other Lenders inrespect thereof, it being acknowledged and

 

-5-   agreed by the parties hereto that any obligation of the Borrower to pay or reimbursethe Lenders in respect of the Outstanding BAs is solely a risk and for the accountof the initial Lenders based upon their respective Commitments as in effect prior toand without regard to the provisions of this Agreement.  (b) Notwithstanding the foregoing, from time to time, as the Outstanding BAs matureand Rollovers and Conversions are made by the Borrower in respect thereof, each of theLenders shall participate in the Loans effecting such Rollovers and Conversions to thefull extent of its revised or new, as applicable, Commitment after giving effect to theprovisions of this Agreement.**4.**     **Representations and Warranties**     The Borrower hereby represents and warrants as follows to each Lender and the Agent andacknowledges and confirms that each Lender and the Agent is relying upon such representations andwarranties: (a) ***Status and Power***    It is a corporation duly incorporated and organized and validly subsisting in goodstanding under the laws of Canada. It is duly qualified, registered or licensed inall jurisdictions where such qualification, registration or licensing is required,except where the failure to be so qualified would not have and would not reasonablybe expected to have a Material Adverse Effect. It has all requisite capacity, powerand authority to own, hold under licence or lease its properties necessary for theconduct of its business and to carry on its business as currently conducted. It hasall requisite corporate capacity, power and authority to enter into and carry outthe transactions contemplated by this Agreement.  (b) ***Authorization and Enforcement***    All necessary action, corporate or otherwise, has been taken to authorize theexecution, delivery and performance by the Borrower of this Agreement. It has dulyexecuted and delivered this Agreement. This Agreement is a legal, valid and bindingobligation of the Borrower enforceable against the Borrower by the Agent and theLenders in accordance with its terms, subject to the qualifications contained in theopinion of the Borrower’s counsel delivered pursuant to Section 5(c).  (c) ***Compliance with Other Instruments***    The execution, delivery and performance by the Borrower of this Agreement and theconsummation of the transactions contemplated herein do not conflict with, result inany breach or violation of, or constitute a default under the terms, conditions orprovisions of the charter or constating documents or by-laws of, or any unanimousshareholder 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 issubject or of any material agreement, lease, licence,

 

-6-   permit or other instrument to which the Borrower is a party or is otherwise bound orby which the Borrower benefits or to which its property is subject and do notrequire the consent or approval of any Governmental Authority or any other party ofwhich the failure to have received or obtained would have or would reasonably beexpected to have a Material Adverse Effect.     The representations and warranties set out in this Agreement shall survive the execution anddelivery of this Agreement and the making of each Drawdown, notwithstanding any investigations orexaminations which may be made by or on behalf of the Agent, the Lenders or Lenders’ Counsel. Suchrepresentations and warranties shall survive until the Credit Agreement has been terminated.**5.**     **Condition Precedent**     The amendments and supplements to the Credit Agreement contained in herein shall be effectiveupon, and shall be subject to, the following conditions precedent: (a) the Borrower shall have paid to the Agent, for each Lender, the fees requiredto be paid pursuant to Section 2.4 hereof;  (b) the Borrower shall have delivered to the Agent a current certificate ofcompliance in respect of its jurisdiction of incorporation, certified copies of itsconstating documents, by-laws and the resolutions authorizing this Agreement and thetransactions hereunder (or a certification there have been no changes to such documentssince May 29, 2008) and an Officer’s Certificate as to the incumbency of the officersthereof signing this agreement;  (c) the Agent and the Lenders shall have received legal opinions from counsel tothe Borrower respecting this Agreement and the transactions contemplated hereby in formand substance as may be required by the Agent, acting reasonably;  (d) no Default or Event of Default shall have occurred and be continuing and therepresentations and warranties contained in Section 8.1 of the Credit Agreement shallbe true and correct in all material respects and the Borrower shall have delivered tothe Agent an Officer’s Certificate confirming the same; and  (e) no consents, approvals or authorizations are required for the increase in theCredit Facility (except for those that have been unconditionally obtained and are infull force and effect, unamended).     The foregoing conditions precedent are inserted for the sole benefit of the Lenders and theAgent and may be waived in writing by the Lenders, in whole or in part (with or without terms andconditions).**6.**     **Confirmation of Credit Agreement and other Loan Documents**     The Credit Agreement and the other Documents to which the Borrower is a party and allcovenants, terms and provisions thereof, except as expressly amended and supplemented by this

 

-7-Agreement, shall be and continue to be in full force and effect and the Credit Agreement asamended and supplemented by this Agreement and each of the other Documents to which the Borrower isa party is hereby ratified and confirmed and shall from and after the date hereof continue in fullforce and effect as herein amended and supplemented, with such amendments and supplements inSection 2 hereof being effective from and as of the date hereof upon satisfaction of the conditionsprecedent set forth in Section 5 hereof.**7.**     **Further Assurances**     The parties hereto shall from time to time do all such further acts and things and execute anddeliver all such documents as are required in order to effect the full intent of and fully performand carry out the terms of this Agreement.**8.**     **Enurement**     This Agreement shall enure to the benefit of and shall be binding upon the parties hereto andtheir respective successors and permitted assigns.**9.**     **Counterparts**     This Agreement may be executed in any number of counterparts, each of which shall be deemed tobe an original and all of which taken together shall be deemed to constitute one and the sameinstrument, and it shall not be necessary in making proof of this Agreement to produce or accountfor more than one such counterpart. Such executed counterparts may be delivered by facsimile orother electronic transmission and, when so delivered, shall constitute a binding agreement of theparties hereto.**[the remainder of this page has intentionally been left blank]**

 

           IN WITNESS WHEREOF the parties hereto have executed this Agreement.      **POTASH CORPORATION OF SASKATCHEWAN INC.**