(Potash story updated with the latest details on BHP Billiton's attempts to win regulatory approval of its bid from the Canadian government.)SASKATOON, Saskatchewan ( TheStreet) -- Potash ( POT) gave itself some ammunition Thursday in its struggle either to scamper away from takeover pursuer BHP Billiton ( BHP) or force the mining giant to pay up. Potash reported third-quarter earnings that exceeded Wall Street expectations, but the company's managers also made a boldly optimistic prediction about Potash's profit next year -- an increase in guidance that the company undoubtedly hopes will force investors to revalue the stock higher. >>Potash vs BHP: The Fertilizer War From A to Z In early trading Thursday, at least, that wasn't the case. Potash shares were falling 4% to $143.31 on heavy volume. The downward move likely had to do with increasing concern that the Canadian federal government has grown more circumspect about approving BHP's bid for Potash. A report in the Globe & Mail newspaper Thursday morning points out that Ottawa officials appear to be swayed more and more by arguments against foreign ownership of crucial natural resources -- this despite Canada's recent history of letting big overseas concerns buy out independent Canadian miners. (See: Vale's ( VALE) acquisition of Inco, 2006.) Uncertainty surrounding the politics of the takeover has investors nervous that Ottawa might scuttle any deal, no matter the price that BHP offers. Ottawa's Investment Canada, the federal agency with jurisdiction over the takeover bid, is scheduled to release its decision next Wednesday, Nov. 3. BHP Billiton had been drawing criticism for making its bid for Potash too late. That's because a serious run-up in crop prices this summer and fall has made farmers flush and eager to load up on fertilizers. The crop rally has lifted the stocks of agriculture companies across the board, including Potash's, with the effect of making BHP's $130-a-share offer look naïve by comparison.