The yen retreated against the dollar on Thursday from a six-week high after China's finance minister quelled speculation that the country was about to let its tightly controlled currency appreciate. The yen and other Asian currencies have gained in the past two weeks on growing expectations China would relax controls on the yuan during this week's Labor Day holidays and let the currency strengthen against the dollar. Even so, yuan revaluation expectations are likely to persist, with speculators simply focusing on other likely dates for a change in the currency regime, she said. "We will actively and prudently push forward this reform but I believe under the current situation that speculation on the renminbi (yuan) exchange rate is very hot and that pushing forward this reform is very difficult," Chinese Finance Minister Jin Renqing said on Wednesday. Jin was speaking on the sidelines of an Asian Development Bank meeting in Istanbul. The yen traded at 104.56 per dollar at 0400 GMT, retreating from a six-week high of 104.21 on Wednesday. It has lost ground against the euro since hitting a 2-1/2-month high of about 134.7 per euro on April 29. It was trading at 135.29 on Thursday. Greg Gibbs, senior currency strategist, at Royal Bank of Canada said yuan reform remained a "hot topic" and the minister's comments did little to dampen expectations. In fact, they could even fan the speculation, he said. The clear implication is that China wants to change the regime, but would prefer to do it calmly, almost without anyone noticing, Gibbs said in a note to clients.