* Miner plans to exercise option to buy Anglo Sur stake * Codelco has law on its side - CEO SANTIAGO, Oct 29 (Reuters) - Chile's giant state miner Codelco says it will defend "with all the necessary tools" its option to buy a 49-percent stake in key properties owned by Anglo American in south-central Chile, Codelco's CEO said in an interview published on Saturday. Codelco, the world's top copper producer, told Chile's regulator on Friday that its board had signed off on its option to buy the stake in Anglo American Sur. It has a 30-day window to exercise the option starting on Jan. 1, 2012. But speculation has arisen that Anglo may seek to thwart the deal, possibly by selling some shares to a third party before January. "We don't have proof they are trying to do this. But if they were, Codelco is in a very solid commercial and legal position" to fight it, Codelco CEO Diego Hernandez told the Chilean newspaper El Mercurio. "This is an asset the company has and our obligation is to defend it with all the necessary tools," he added. Hernandez said once the deal went through, Anglo American would have to pay between $850 million and $900 million in taxes. The option gives Codelco a stake in Anglo's properties in southern Chile, which include the flagship Los Bronces expansion project, El Soldado mine, the Chagres smelter and Los Sulfatos and San Enrique Monolito exploration projects. Codelco said earlier this month it had secured a $6.75 billion bridging loan from Japan's Mitsui & Co to allow it to exercise its option.
