ISLAMABAD (Reuters) - Tethyan Copper, which owns the massive Reko Diq copper-gold project in the Balochistan province of Pakistan, said it has begun international arbitration proceedings in order to protect its rights after the province rejected its mining lease application. Tethyan, a joint-venture between Chiles Antofagasta and Canadas Barrick Gold, said it has begun arbitration proceedings, but it remains open to an amicable, negotiated resolution to the dispute. Earlier this month, Balochistan rejected the mining lease application (MLA) that had been submitted by Tethyan in February. This came just weeks after Tethyan filed a notice of dispute, after provincial officials refused to meet with its executives, or extend a deadline for a response to objections raised over the lease. We are disappointed we have not yet been given the opportunity to resolve this by negotiation. We firmly believe that our feasibility study and MLA submission are in accordance with the Balochistan Mineral Rules 2002, said Tethyan Chief Executive Tim Livesey in a brief statement on Tuesday. Tethyan did not provide any details on the arbitration proceedings. Barrick and Antofagasta have already invested over $220 million in the Reko Diq project and the two companies jointly own a 75 percent stake in the project, with the government of Balochistan owning the remainder. The project, seen costing more than $3 billion, is expected to generate a huge amount of foreign direct investment into the country.