The public pension fund said it may become a net seller of bonds to cover payments in the world's fastest aging society.

The Government Pension Investment Fund forecast in September that it would sell ¥4 trillion in assets in the business year ending March 31 to fund payouts. Sales may be less than that in the year starting April 1 as bonds reach maturity, said Takahiro Mitani, president of the fund, known as GPIF.

Overseeing ¥117.6 trillion, the fund is the world's largest.