LONDON (AFP) - The dollar rebounded Wednesday from a 15-year low against the yen after Japans finance minister toughened his rhetoric to say he would take proper measures to curb the currencys rise if necessary. In morning London deals, the greenback rose to 84.65 yen from 84.06 late in New York on Tuesday, when it had plunged to 83.61 yen a level that was last seen in June 1995. The euro climbed to 107.29 yen, after slumping on Tuesday to 105.44 yen to reach the lowest point since 12 July 2001. This week, the dollar has tumbled against the safe-haven yen as Japanese officials had appeared unwilling to act against the currencys strength, which threatens the countrys exporters, amid frustration over perceived inaction. The Japanese unit has also rallied because it is widely regarded as a safe investment and draws strength from the uncertain economic outlook and recent dire US economic data, including news of plunging existing home sales. Japans Finance Minister Yoshihiko Noda cautioned the market on Wednesday, telling reporters that the Japanese authorities must take proper measures when necessary. He did not mention specific options but the comment followed a report in the Nikkei economic daily that his ministry was ready to make a solo intervention if speculative trade boosts the Japanese currency by a few yen in a day. The yen has weakened marginally against most currencies today in response to the more direct comment from Finance Minister Noda in regard to the yen, said Derek Halpenny, European head of global currency research at The Bank of Tokyo-Mitsubishi UFJ in London. The much-used phrase by previous Minstry of Finance officials prior to actual intervention that appropriate action would be taken when needed is another step toward the authorities actually intervening. For every one-yen rise in the currencys value against the dollar, Japans exporters can lose tens of billions of yen earned overseas when repatriated, threatening a sector that Japan depends on to offset its weak domestic picture. The dollar hit the latest yen low on Tuesday after data showed US existing home sales plunged 27.2 percent in July to a 11-year low which was much worse than forecast and stoked fears the US recovery was at risk. Elsewhere on Wednesday, the euro rose against the dollar on news that German business confidence has regained levels not seen since before the global financial crisis, according to the Ifo economic institute. The Ifos climate index climbed to 106.7 points in August from 106.2 points in July. That beat market expectations for a slight decline and marked the highest level since June 2007. In London trade on Wednesday, the euro changed hands at 1.2688 dollars against 1.2670 dollars on Tuesday, at 107.29 yen (106.47), 0.8228 pounds (0.8214) and 1.3038 Swiss francs (1.3059). The dollar stood at 84.56 yen (84.06) and 1.0276 Swiss francs (1.0306). The pound was at 1.5420 dollars (1.5414). On the London Bullion Market, the price of gold rose to 1,237.90 dollars an ounce from 1,222.00 dollars an ounce on Tuesday.