SYDNEY (Reuters) - Canada's Saputo Inc (>> Saputo Inc.) has raised its stake in takeover target Warrnambool Cheese and Butter Factory Holdings Co (>> Warrnambool Cheese & Butter Factory Co.) to 20.1 percent, the company said on Thursday, making it the biggest shareholder just ahead of its offer deadline on Friday.

Saputo is battling with Local bidder Murray Goulburn Co-operative Co Ltd for Australia's oldest dairy firm, eyeing a platform for rapidly growing sales of both traditional dairy products and high-tech milk extracts to China.

Saputo's unconditional cash offer of A$515 million ($461 million) will rise as high as A$549 million ($492 million) if it receives acceptances of 90 percent or more of Warrnambool shareholders.

Murray Goulburn, with its A$530 million ($474.96 million) offer, is waiting for a regulatory decision and said it may increase its stake in Warrnambool via market purchases.

Saputo has not extended its offer, which is due on Friday, although analysts expect the company to extend the offer period.

Saputo needs to win over former bidding rival Bega Cheese Ltd (>> Bega Cheese Ltd), which pulled out of the race in December, or Japanese beverage giant Kirin Holdings Co Ltd (>> Kirin Holdings Company, Limited.).

(Reporting by Maggie Lu Yueyang; Editing by Dan Grebler)