Japan's Finance Minister Taro Aso has indicated the country's financial authorities are ready to take action to prevent the yen from surging. Taro Aso spoke to reporters on Tuesday after the Japanese currency hit a one-month high of 105 yen against the dollar. Investors are buying the yen to avoid risks over the June 23rd British referendum on the country's EU membership. 

    Aso said he is keeping an eye on how the vote will affect financial markets. He added that currency fluctuations are not desirable and market stability is extremely important.

    Aso said financial authorities will try to ensure that speculative trading doesn't last. He said they will take action, if necessary, in line with agreements made with other Group of 7 and Group of 20 members, according to Japan's (NHK WORLD) radio.

    The stronger yen is causing Japanese share prices to fall due to worries that exporters' earnings will worsen. Investors are also buying Japanese government bonds, sending their yields to record lows.