Brazilian mining mammoth Vale SA (VALE) said Friday that due to the superior option of organically growing its own fertilizer assets, the company hadn't made any proposal on acquiring companies in the sector, Vale said in a statement Friday.

The statement was a reaction to Thursday's Brazilian press report that Vale was looking at further acquisitions of potassium assets.

Citing market sources, the Estado newspaper said Vale was targeting Mosaic (MOS), which is controlled by Cargill and IMC Global (IGL).

Vale on Thursday declined to comment on the company's alleged interest in Mosaic.

Mosaic is valued at $25 billion, Estado said, and is the world's largest phosphates producer and one of the world's largest potassium miners.

Earlier this year Vale paid $857 million for potassium mining assets in Argentina and Canada.

Vale CEO Roger Agnelli had previously said Vale was interested in developing its potassium-mining business to supply Brazilian agriculture's large and growing appetite for fertilizers.

According to the Estado report, Vale's global mining rival BHP Billiton (BHP) was also likely to compete for Mosaic.

-John Kolodziejski, Dow Jones Newswires; 55-21-2586-6086; John.Kolodziejski@dowjones.com