Australia's Westpac Banking Corp said on Thursday it will sell its lenders mortgage insurance (LMI) business to Arch Capital Group in a deal that will also make Arch Westpac's exclusive LMI supplier for 10 years. The sale, which is expected to close by the end of August, is the latest step in Westpac's efforts to simplify its operations and cut costs by focusing on its core domestic and New Zealand businesses. Westpac, Australia's third largest lender, said it will record a loss on the sale, though the deal is expected to add about seven basis points to its common equity tier 1 capital ratio.