MELBOURNE, Australias (

TheStreet

) --

BHP Billiton

(BHP) - Get Report

on Sunday withdrew its $40 billion offer to buy

Potash Corp. of Saskatchewan

(POT)

because of government opposition.

BHP said it will restart buying back $4.2 billion of stock, part of a $13 billion buyback program it suspended in 2007.

The Ottawa government said earlier this month it would block the deal to buy Potash, the world's largest fertilizer maker, because it wasn't a net benefit to Canada. BHP had 30 days to appeal, but said Sunday in a statement that it cannot satisfy the net benefit requirements outlined by the government.

"We have not been able to obtain clearance under the Investment Canada Act and have accordingly decided to withdraw the Offer," BHP Billiton CEO Marius Kloppers said, in a statement Sunday.

BHP said it would recognize a transaction cost of about $350 million, of which about $250 million related to a $45 billion acquisition financing facility, as an exceptional item in its December interim accounts.

BHP said the offer and the benefits to Canada would have been "unparalleled in substance, scope and duration."

Had the deal been approved by the government and shareholders, it would have been one of the biggest in Canadian history -- and the largest in the world this year.

-- Written by Joseph Woelfel

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