Japan's Prime Minister Fumio Kishida, on platform, delivers his policy speech at parliament in Tokyo on Jan 30, 2024. (PHOTO / KYODO NEWS VIA AP)

TOKYO - Japan faces more than a two-fold increase in annual interest payments on government debt to 24.8 trillion yen ($169 billion) over the next decade, draft government estimates seen by Reuters showed on Friday.

The latest estimate, prepared by the Ministry of Finance for parliament ahead of debate on the government's budget bills, served as a reminder that the costs of financing debt could shoot up as the central bank leans toward exiting crisis-mode stimulus.

As the first step toward fixing tattered public finances, the government vowed to bring the primary budget for national and local governments combined to a surplus by the fiscal year ending in March 2026, a target analysts describe as a tall order

Years of the Bank of Japan's unconventional policy, such as negative interest rates, has kept borrowing costs ultra low, effectively bankrolling government debt.

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However, interest payments on government debt are expected to jump to 24.8 trillion yen in fiscal 2033, which ends in March 2034, versus 9.83 trillion yen for the fiscal year ending in March 2025, the draft estimate showed.

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Japan's public debt stands at more than twice the size of its economy, by far the worst among industrial world.

The latest estimate shows that the government will be saddled with record outstanding debt of 1,244.68 trillion yen at the end of March 2034.

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As the first step toward fixing tattered public finances, the government vowed to bring the primary budget for national and local governments combined to a surplus by the fiscal year ending in March 2026, a target analysts describe as a tall order.

The primary budget balance, which excludes new bond sales and debt-servicing costs, is a key gauge of how much policy measures can be financed without issuing debt.