* Japan intervenes for first time in 6-½ yrs
* Dollar/yen rises 1.6 pct
* Noda says will continue to take decisive action
TOKYO, Sept 15 (Reuters) - The dollar jumped against the yen on Wednesday after Japan intervened in the currency market for the first time in 6-½ years to stem the yen's persistent strength.
Finance Minister Yoshihiko Noda said Japan intervened in the currency market as the impact of the yen's rise on the economy could not be ignored, adding that Japan will continue to take decisive action.
"We will take decisive steps if necessary, including intervention, while continuing to closely watch currency market moves from now on," Noda told reporters at a hastily arranged news conference.
The Bank of Japan also said it will provide ample funds to markets while keeping very easy monetary conditions.
The dollar rose about 1.6 percent to around 84.33 yen, as intervention triggered a wave of stop-loss buying in the dollar.
Earlier the greenback hit a 15-year low of 82.87 yen as the dollar was hurt by talk that the Federal Reserve could be nearing more quantitative easing.
"I guess the Japanese authorities may want to bring the dollar/yen up to around 85 yen," said a trader at a Japanese financial institution.
Japan has not intervened in currency markets since March 2004, when it ended its 15-month campaign to sell the yen in currency markets.
The yen had gained fresh momentum on Tuesday after Japanese Prime Minister Naoto Kan won a leadership ballot against a rival seen as more willing to intervene against the yen.
The yen also weakened more than one percent against other major currencies. The Australian dollar rose to around 79.30 yen, its highest in more than five weeks.
The euro rose about 1.6 percent to around 109.65 yen. (Editing by Edwina Gibbs)