TOKYO, Japan—Japan plans an extra stimulus of at least $31 billion this fiscal year that would include measures to tackle the surging yen and weak share prices, the top government spokesman said Monday.

The government needs to take "policy action in view of the strengthening yen and problems surrounding share prices" and plans spending of "no less than 2.7 trillion yen ($31 billion)," said government spokesman Hirofumi Hirano.

Japanese share prices have been hit in recent weeks by a strong yen which hit a 14-year high against the dollar last week.

A strong yen hurts exporters by making their goods more expensive abroad and eating into their dollar profits when they are converted back into yen.

The yen traded at 86.74-yen to the dollar in Tokyo early Monday.