Jan 29 (Reuters) - Mastercard posted a rise in fourth-quarter profit on Thursday, as sustained consumer spending drove up its transaction ​volumes. Household spending has remained resilient despite tariff-fueled uncertainty, as ‌consumers continue to spend on necessities. During the holiday quarter, shoppers also locked in deals ‌to stretch their discretionary budgets, lifting transaction volumes for processors. U.S. banks have seen their credit card balances edge up in the latest quarter, signaling sustained borrowing demand ​despite high interest rates. Mastercard has also been shoring up its diversification push with services such as fraud protection and cybersecurity tools - typically higher margin products.