The dollar was lower against the yen in early Asian trading on Wednesday, after U.S. Federal Reserve Chairman Alan Greenspan acknowledged the day before that low U.S. interest rates might indicate economic weakness. The dollar was trading at 106.60 yen on Wednesday morning, down 0.19 yen from late Tuesday in Tokyo but above the 106.54 yen it bought in New York later that day. The euro rose to $1.2306 early Wednesday from $1.2292 late Tuesday but fell to 131.24 yen from 131.53 yen. In a satellite address to a central bankers' conference in Beijing on Tuesday, Greenspan said he didn't have a good reason to explain persistently low long-dated Treasury yields but that history suggests financial markets possibly expect economic weakness ahead. Forecasts for a weaker U.S. economy usually hurt the dollar, as investors shift cash from U.S. securities to other markets. The dollar was weaker against other Asian currencies. Тhe British pound rose to $1.8345 from $1.8238 late Monday, the day Britain's government announced plans to postpone its own referendum on the EU constitution. Separately, an assessment Tuesday by the International Monetary Fund said a good exchange rate for the euro was between $1.20 and $1.30. "Basically, we would expect some fluctuations in rates around that level, and for that not to create difficulties," said Michael Deppler, who directs the IMF's European department. "The euro needs to adjust to an average rate of around that magnitude." In a conference call, Deppler said the euro remained strong and was benefiting from changes in the euro zone to keep it viable. "Reforms have paid off in past, and there is no reason not to expect them to continue to pay off in the future," he said. Though an economically weak country's departure from the European Monetary Union would leave it free to set lower interest rates and improve its competitiveness by devaluing its currency, the advantages would not last, said Joerg Kraemer, chief economist at HVB Group. "If a country abolished the euro and pursued a policy of cheap money, bond yields and thus financing costs for the government and for companies would surge. This, in turn, would jeopardize the very existence of many companies," Kraemer said. "Foreign direct investments, which are so critical for economic growth, would dry up."