BHP Billiton, the worldÔÇÖs largest mining company, has agreed to buy Canadian potash developer Athabasca Potash Inc. (API) for C$341 million ($320 million). The deal follows news of Brazilian miner Vale's $3.8 billion acquisition on Tuesday of food conglomerate Bunge's Brazilian assets, which are primarily focused on phosphate and fertilizers. BHP signaled its interest in the potash sector by its acquisition of Anglo Potash in 2008.

