TORONTO - Canadian fertilizer producer Agrium Inc (AGU.TO) extended its hostile bid for rival CF Industries (CF.N) on Monday and said it was sure it would have the money needed to complete the purchase.

Calgary, Alberta-based Agrium said its $45-per-share cash-and-stock offer for the U.S. company would now expire on January 22. It had been scheduled to expire on December 18.

Agrium also said it had replaced its financing commitments with highly confident letters from Royal Bank of Canada (RY.TO) and the Bank of Nova Scotia (BNS.TO).

A condition of Agrium's offer is that the company has sufficient funding as well as cash on hand to purchase the outstanding shares and pay other expenses.

CF, which has been fending off Agrium's overtures since February, is itself locked in a hostile campaign to acquire U.S. fertilizer maker Terra Industries (TRA.N).

Agrium's $5 billion bid is contingent on CF dropping its takeover offer for Terra.

Earlier this month Agrium said it planned to nominate a slate of directors to stand for election at CF's 2010 annual shareholder meeting.

($1=$1.05 Canadian)

(Reporting by Scott Anderson; Editing by Lisa Von Ahn)