BHP calls off move for Potash and goes ahead with share buyback

BHP also signalled with its revived $4.2bn share buyback that it had limited opportunities for other major acquisitions. Shareholders will be eager to hear what further growth prospects the company will pursue with its cash pile when BHP chief executive Marius Kloppers addresses the group's annual meeting in Australia today.

"Certainly the best investment is probably in themselves at the moment," said Brendan James, a partner at BHP shareholder Perennial Growth, referring to the prospect of a bigger buyback.

Canada blocked BHP's hostile bid for the world's largest fertiliser maker on November 3 and gave BHP a month to prove the takeover would benefit Canada.

"Unfortunately, despite having received all required anti-trust clearances for the offer, we have not been able to obtain clearance under the Investment Canada Act and have accordingly decided to withdraw the offer," Mr Kloppers said in a statement.

Analysts said it would be hard for the world's largest miner to chase other major deals, given its size and dominance in most of its markets. "I think the regulatory environment is very difficult to negotiate when you are as big as BHP," said Tim Schroeders, a portfolio manager at Pengana Capital, who has shares in BHP.

Analysts said BHP may look at takeovers in the petroleum sector.

"For us the two most obvious potential targets are Woodside Petroleum and Anardarko Petroleum, while outside of oil and gas we also feel an acquisition of Freeport would have its merits," said Dominic O'Kane at Liberum Capital in London.

BHP failed to buy Rio Tinto in 2008 and also called off plans for a joint venture with the same firm last month after trouble securing regulatory approval.