Japanese officials won't intervene further in the currency market unless they see evidence of speculative buying strengthening the yen, according to Naomi Fink, head of Japan strategy at Jefferies Japan Ltd.

The Finance Ministry and the Bank of Japan won't repeat their tactic of selling yen in an effort to weaken the currency, as they did in March following the nation's worst earthquake on record, unless it becomes clear that market activity is being driven by speculators instead of institutional investment, Fink said during Bloomberg Link's Japan Conference in New York. The yen dipped below 80 versus the dollar Monday, increasing speculation the BOJ would intervene, as it did March 18 in conjunction with other Group of Seven nations. The yen surged following the quake-tsunami disaster, reaching a postwar high of ¥76.25 March 17, amid speculation Japanese investors would repatriate assets to pay for reconstruction.