The government expects its interest payments on outstanding debt to roughly double over the next four years as the Bank of Japan¡¯s gradual rate hikes push up borrowing costs.

Interest payments are projected at ?21.6 trillion ($139 billion) in the year starting April 2029, up from the current year¡¯s budgeted ?10.5 trillion, according to a Finance Ministry document released Thursday. The projections assume annual nominal economic growth of 3%.

Overall debt-servicing costs are seen rising about 46% to ?41.3 trillion during the same period. That would account for about 30% of total projected spending of ?139.7 trillion in fiscal 2029, topping expected outlays for social security.