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SYDNEY, Jan 30 (Reuters) - Canadian dairy company Saputo Inc SAP.TO said on Monday it will make an all-cash takeover offer for the 12 percent of Australia's Warrnambool Cheese and Butter WCB.AX it does not already own, valuing the company at A$682 million ($515 million).
The A$8.85 per-share offer is at a 24.8 percent premium to Warrnambool's Friday closing price of A$7.09.
Shares in Warrnambool rose as much as 23.7 percent following the announcement, their biggest one day gain since September 2013. The stock was up 22 percent to A$8.65 a share by 0021 GMT.
Saputo, which already owns 88.02 percent of Warrnambool shares, will fund the acquisition from cash on hand and existing credit facilities, the company in a statement to the Australian Securities Exchange.
"Saputo have been aiming for full ownership but there has been that block stake there for a while," said Michael Harvey, senior dairy analyst at Rabobank.
Saputo acquired its majority stake in Warrnambool Cheese and Butter in 2014, beating local rivals Murray Goulburn Ltd MGC.AX and Bega Cheese Ltd BGA.AX in one of the Australia's most hotly contested takeover battles.
Saputo's offer is the latest in a series of M&A deals in the Australian dairy industry this year.
Bega earlier this month agreed a $460 million deal to acquire Mondelez International's MDLZ.O grocery brands in Australia and New Zealand. ($1 = 1.3233 Australian dollars)