Health, Labor and Welfare Minister Norihisa Tamura requested Friday that Japan's ¥129 trillion pension fund revise its investment portfolio, which is dominated by domestic bonds, ahead of schedule.

The Government Pension Investment Fund, which manages investment of reserve funds for public pension plans, is expected to review its fund management plan this fall ahead of the original deadline in March and will be encouraged to invest more funds in the domestic stock market under the revised portfolio standards.

Prime Minister Shinzo Abe also called for the revision when he discussed the matter with Tamura on Friday. The GPIF is one of the world's largest institutional investors.

The current portfolio standard set by an expert committee and approved by the welfare minister requires only 12 percent of the GPIF to be invested in the domestic stock market, compared with the 60 percent it has sunk into domestic bonds.

At the end of 2013, 55.22 percent of GPIF's investment was in domestic bonds, 17.22 percent in domestic stocks, 10.60 percent in foreign bonds and 15.18 percent in foreign stocks.