Just days after Sociedad Química y Minera de Chile (NYSE:SQM) released less-than-stellar Q1 results, the company was dealt another blow. Potash Corporation of Saskatchewan (TSX:POT,NYSE:POT) revealed on May 21 that it is re-evaluating whether to keep its stakes in both SQM and Israel Chemicals (NYSE:ICL). PotashCorp CEO Jochen Tilk spoke at a BMO (TSX:BMO,NYSE:BMO) investor conference in New York on Thursday about the various companies it holds interests in, including Sinofert Holdings (HKEX:0297) and Arab Potash Company, both of which he considers "strategic" and beneficial. However, looking at SQM and ICL, Tilk said that if PotashCorp can't build on the majority stakes it has, it may not keep them. As it stands, the company has very little say in how SQM and ICL do business, while it has control over marketing and sales for both Sinofert and Arab Potash. PotashCorp made a long-winded attempt to acquire ICL in 2013 under former CEO Bill Doyle. However, after six months it abandoned the plan. That may be why Tilk is treading lightly — he said at the conference that his intent was not to signal any plans for investments in either. "We can't be counter-productive by doing or acting (to) impair the value of the companies. Timing is everything," Tilk said. Reacting to that statement, ICL CEO Stefan Borgas said in an interview that if PotashCorp wants to increase its stake in the company, it should be direct with Israel's government and Israel (TLV:ILCO), ICL's biggest stakeholder. "Our advice would always be for anybody who has these kind of interests, not just in ICL, but in general, is be as specific as you possibly can so there is actually a concrete proposal on the table, rather than just discussing concepts," he said.