(Adds detail on stake, background)
June 13 (Reuters) - Australian billionaire Gina Rinehart's Hancock Prospecting Pty Ltd group of companies disclosed on Wednesday a 19.96 percent stake in Atlas Iron Ltd AGO.AX , heating up the race for the small iron ore miner.
Hancock Prospecting Pty Ltd holds a 14.97 percent stake in Atlas, while Hancock's unit Redstone Corporation Pty Ltd will have a 4.99 percent interest in the Perth-based miner.
The move comes a week after Fortescue Metals Group FMG.AX said it has built a 19.9-percent interest in Atlas Iron, giving it a large enough stake to block a A$280 million ($212.07 million) takeover of Atlas by Mineral Resources Ltd MIN.AX . mining infrastructure group Mineral Resources MIN.AX responded to Fortescue, by allowing Atlas to hold talks with other potential buyers. April, Mineral Resources agreed to buy Atlas via a scheme of arrangement, saying at the time that the amalgamation of its existing iron ore assets in the Pilbara region with those of Atlas would lead to cost savings. is a hot target for takeover by Fortescue due to its North West Infrastructure (NWI), which the firm's joint venture with Brockman Mining 0159.HK and FerrAus has a capacity to export 50 mln tonnes per annum (Mtpa) from Port Hedland, UBS said in a statement last week. ($1 = 1.3203 Australian dollars)