LONDON/SANTIAGO, Jan 10 (Reuters) - Codelco, the world's largest copper producer, asked a Chilean court to enforce its disputed option to buy a 49 percent stake in Anglo American's south Chilean assets, suing the global miner and claiming damages for breach of contract.
Tuesday's suit is the latest escalation in an increasingly bitter and complex legal row between the two mining powerhouses.
The Chilean state miner said in October it planned to exercise its long-standing option to take a minority stake in Anglo American Sur, but it was caught out by Anglo's surprise sale of a stake to Japan's Mitsubishi Corp a month later.
Anglo says the sale of a 24.5 percent stake in the assets to Mitsubishi for $5.4 billion halved Codelco's option to buy a 49 percent stake in the properties. Codelco, which viewed the pre-emptive move as a snub, disputes that.
Codelco dug in its heels last week, stating on Jan. 2 -- the day the option window opened -- that it exercised its option to buy a 49 percent stake in Anglo's key properties for an estimated price of around $6 billion.
Anglo, which is separately suing Codelco for breach of contract, has said it is not obliged to sell any shares in Anglo American Sur to Codelco.
Codelco said Tuesday's lawsuit requested damages from Anglo for breach of contract, including the payment of dividends from the shares Codelco says it has a right to own.
The mining giant says it is committed to taking the 49 percent stake, or if the court rules against it, a 24.5 percent stake plus a sum equivalent to the further 24.5 percent. As a final alternative, it would seek compensation equivalent to the whole 49 percent it could have bought under the original option.
Codelco also said it had begun proceedings to request the disclosure of the full details of Anglo's sale deal with Mitsubishi, with the aim of exploring further legal action.
It has separately withdrawn an injunction to stop further stake sales by Anglo -- a suit which had been intended to protect Codelco's right to buy -- arguing the option is now exercised.
"We regret that Codelco has been forced to take legal action. However, this is the only possible option when a counter party is acting erratically and in clear violation of the contracts," Diego Hernandez, Chief Executive of Codelco, said.
"Anglo American's actions severely compromise the interests of its shareholders in the short and medium term."
The head of Anglo's operations in Chile, Miguel Angel Duran, declined comment on Tuesday.
Anglo's properties in southern Chile include the flagship expansion project Los Bronces, where Anglo has invested around$2.8 billion; the El Soldado mine; the Chagres smelter; and the Los Sulfatos and San Enrique Monolito exploration projects.
Many analysts welcomed the Mitsubishi deal, arguing that faced with the need for a sale, Anglo secured a better price than it would have done by selling to Codelco, whom it has long sought to buy out of the option.
But industry commentators and some shareholders are fretting that the pursuit of shareholder value in the short and medium term could leave lasting scars on Anglo's crucial relationship with Chile, the world's largest copper producer.
A court battle is already priced in, analysts say, but an eventual settlement is a widely expected outcome. Anglo has said it is open to a commercial settlement.
"It is too big for either party to let go," mining analyst Cailey Barker at Numis Securities in London said.