South Korea's Financial Services Commission plans to expand high-risk mortgage categories from January next year and apply heavier risk weights to expensive, high-DSR and high-LTV home loans, a change that could curb new lending and will also apply to existing balances. The policy debate has intensified as banking data showed KB Kookmin Bank and Shinhan Bank held a combined roughly 10.9 trillion won in mortgages with loan-to-value ratios of 80% or higher at the end of June, while regulators and policymakers scrutinize the risks and possible use of some loans for home purchases.